EconomicsCBSE Class 12 · Money and Banking

Central Bank Functions and Instruments of Monetary Policy (Class 12)

Updated 15 October 2026 · Fact-checked

The Reserve Bank of India, India's central bank since 1935, issues currency, acts as banker to the government and to banks (lender of last resort), keeps foreign exchange reserves and controls credit. Its monetary policy tools are bank rate, repo and reverse repo rates, CRR, SLR and open market operations (quantitative), and margin requirement and moral suasion (qualitative).

Understand Central Bank Functions and Instruments of Monetary Policy

Central bank. Almost every country has one; India's is the Reserve Bank of India (RBI), set up in 1935.

Functions of the central bank (the syllabus names the first four; NCERT adds the fifth).
1. Bank of issue: sole authority to issue currency. Currency held by the public and banks is high-powered money (reserve money, monetary base), the basis of credit creation.
2. Government's bank: acts as banker to the government, managing its accounts and borrowing.
3. Banker's bank: commercial banks keep reserves with it; it stands ready to lend to banks at all times, so it is the lender of last resort.
4. Controller of credit: regulates money supply and credit through the instruments below.
5. Custodian of foreign exchange reserves of the economy.

Quantitative instruments (control the volume of credit):

Bank rate: the rate at which the RBI lends to commercial banks. A higher bank rate makes borrowing by banks costlier, reduces their reserves and reduces money supply; a lower rate increases it.
Repo rate: the rate at which the RBI lends to banks through a repurchase agreement (RBI buys securities with an agreement to resell them at a set date and price). Repo and reverse repo operations (overnight, 7-day, 14-day) have become the RBI's main tool.
Reverse repo rate: the rate at which the RBI absorbs (borrows) money from banks by selling securities with an agreement to buy them back.
Cash Reserve Ratio (CRR): the percentage of deposits banks must keep as cash reserves (with the RBI). Higher CRR → smaller money multiplier (1 ÷ LRR) → less credit.
Statutory Liquidity Ratio (SLR): the percentage of deposits banks must keep in liquid form (cash, gold, approved securities) with themselves. Higher SLR → less lendable funds.
Open market operations (OMO): buying and selling government bonds in the open market. Buying injects reserves and raises money supply; selling withdraws reserves and reduces it. Outright OMOs are permanent; repo operations are temporary.

Qualitative instruments (direct credit to or away from uses):

Margin requirement: the difference between the value of a security pledged and the loan given against it. Raising the margin cuts the loan per rupee of security.
Moral suasion: persuading banks to encourage or discourage lending.

Tool	To control inflation (reduce credit)	To fight deflation (expand credit)
Bank rate / repo rate	Raise	Lower
Reverse repo rate	Raise	Lower
CRR / SLR	Raise	Lower
Open market operations	Sell securities	Buy securities
Margin requirement	Raise	Lower
Moral suasion	Discourage lending	Encourage lending

Worked effect of CRR (our figures). With LRR 10%, an initial deposit of ₹4,000 crore can support total deposits of 4,000 ÷ 0.10 = ₹40,000 crore. If the ratio is cut to 8%, the multiplier rises from 10 to 12.5 and total deposits to ₹50,000 crore.

Central Bank Functions and Instruments of Monetary Policy: key facts

Money multiplier: Money multiplier = 1 ÷ LRR (legal reserve ratio); Higher CRR → smaller multiplier.
Total deposits: Total deposits = Initial deposit × 1 ÷ LRR; Used to show CRR effects.
Margin: Loan = Value of security × (1 − margin); Higher margin → smaller loan.
Direction rule: Inflation: raise rates and ratios, sell bonds; deflation: lower rates and ratios, buy bonds; OMO is the only tool where 'sell' means tight.
Repo vs reverse repo: Repo: RBI lends to banks; Reverse repo: RBI absorbs funds from banks; Repo = rate on loans from RBI.

How to answer Central Bank Functions and Instruments of Monetary Policy questions

This is the most-asked Money and Banking topic: 1-mark tool identification, 3- or 4-mark 'how can the RBI control inflation/deficient demand' questions, and functions of the central bank.

1Decide the aim: reduce money supply (inflation, excess demand) or increase it (deflation, deficient demand).
2For each tool, state the direction (raise/lower; buy/sell) and the chain: cost or availability of credit → borrowing → spending.
3For repo vs reverse repo, remember who lends: in repo the RBI lends; in reverse repo it absorbs.
4For CRR numericals, use multiplier = 1 ÷ LRR and total deposits = initial deposit ÷ LRR.
5For functions, write the five syllabus functions with a line each.

Central Bank Functions and Instruments of Monetary Policy in real life

The idea, met in an everyday situation. Answer the question in your own words, then compare with the model answer. The one-line hook is what to remember.

Repo rate and your EMI

Suppose prices of food and fuel have been rising fast for months. The RBI raises the repo rate. A month later, your uncle's bank tells him the interest on his new car loan will be higher.

Explain the chain from the repo rate to your uncle's loan and to inflation.

Try it first, then show the solutionSolution

Higher repo rate: banks pay more to borrow from the RBI.
Banks pass on the cost: loan rates rise.
People borrow and spend less; demand cools; inflationary pressure eases.

Answer: A higher repo rate raises banks' cost of funds, so they charge more on loans. Costlier credit reduces borrowing and spending, which helps control inflation. That is why his car-loan rate rose.

Memory hook: Repo up, EMIs up, spending down.

Open market operations

Imagine the economy is in a slump: factories are idle and banks are short of funds to lend. The RBI buys government bonds worth ₹500 crore from banks.

How does this help, and by how much could deposits rise if the reserve ratio is 10%?

Try it first, then show the solutionSolution

RBI pays banks for the bonds: bank reserves rise by ₹500 crore.
With more reserves, banks can lend more.
Maximum rise in deposits = 500 ÷ 0.10 = ₹5,000 crore.

Answer: Buying bonds injects ₹500 crore of reserves, letting banks lend more; with a 10% reserve ratio, deposits could rise by up to ₹5,000 crore, raising money supply and demand.

Memory hook: RBI buys, money flies in.

Tricks to remember Central Bank Functions and Instruments of Monetary Policy

Short memory aids. Say each one aloud once, then use it on a question the same day.

B-G-B-C-C
Bank of issue, Government's bank, Banker's bank, Controller of credit, Custodian of forex.
Use it when: Five central bank functions.
Inflation: up, up, sell
Rates up, ratios up, sell bonds, margins up.
Use it when: Anti-inflation measures.
Repo = RBI gives
Repo: RBI gives money (lends). Reverse repo: the reverse, RBI takes money (absorbs).
Use it when: Repo vs reverse repo.

Central Bank Functions and Instruments of Monetary Policy: solved examples

Ordered from board level to HOTS. Try each one before you open the solution.

Example 1: Lender of last resort · 1 mark · MCQBoard level

The RBI's role of being ready to lend to commercial banks at all times is called:
(a) Bank of issue
(b) Custodian of foreign exchange
(c) Lender of last resort
(d) Government's bank

Try it first, then show the solutionSolution

Ready to lend to banks at all times = lender of last resort.

Answer: (c) Lender of last resort

Example 2: Controlling inflation · 4 marks · Short answerBoard level

Explain how the RBI can use (i) the repo rate and (ii) open market operations to control inflation. (4 marks)

Try it first, then show the solutionSolution

Repo rate: raise it; banks' cost of borrowing rises; loan rates rise; credit and demand fall (2 marks).
OMO: sell government securities; reserves of banks fall; lending capacity falls (2 marks).

Answer: (i) The RBI raises the repo rate, the rate at which it lends to banks. Borrowing from the RBI becomes costlier, so banks raise their lending rates; people and firms borrow and spend less, reducing demand and inflationary pressure. (ii) The RBI sells government securities in the open market. Buyers pay from their bank balances, so banks' reserves fall, their capacity to lend falls, and money supply contracts.

Example 3: Effect of a CRR change · 3 marks · Short answerHarder board level

Commercial banks hold reserves of ₹2,000 crore. The CRR is raised from 4% to 5%. Calculate the maximum deposits these reserves can support before and after, and comment. (3 marks)

Try it first, then show the solutionSolution

Before: 2,000 ÷ 0.04 = ₹50,000 crore (multiplier 25).
After: 2,000 ÷ 0.05 = ₹40,000 crore (multiplier 20).
Money supply capacity falls by ₹10,000 crore: a contractionary step.

Answer: Before ₹50,000 crore; after ₹40,000 crore. The multiplier falls from 25 to 20, so the banking system's capacity to create deposits falls by ₹10,000 crore, reducing money supply.

Example 4: Margin requirement · 3 marks · Short answerHarder board level

A trader pledges shares worth ₹10 lakh to borrow from a bank. Find the maximum loan if the margin requirement is 30%, and if the RBI raises it to 40%. What is the purpose of the change? (3 marks)

Try it first, then show the solutionSolution

30%: loan = 10 × 0.70 = ₹7 lakh.
40%: loan = 10 − 4 = ₹6 lakh.
Purpose: discourage credit for that use (qualitative control).

Answer: At 30% margin the loan is ₹7 lakh; at 40% it is ₹6 lakh. Raising the margin reduces the credit available per rupee of security, discouraging borrowing for that purpose (e.g. speculation).

Example 5: Repo vs reverse repo · 3 marks · Short answerHOTS / competency

Distinguish between the repo rate and the reverse repo rate, and state how each would be changed to curb excess demand. (3 marks)

Try it first, then show the solutionSolution

Repo: RBI lends to banks against securities under a repurchase agreement.
Reverse repo: RBI absorbs money from banks by selling securities with an agreement to buy back.
Excess demand: raise both.

Answer: Repo rate: the rate at which the RBI lends to commercial banks through repurchase agreements. Reverse repo rate: the rate at which the RBI absorbs (borrows) funds from banks through reverse repurchase agreements. To curb excess demand, the RBI raises the repo rate (credit costlier) and the reverse repo rate (banks prefer parking funds with the RBI rather than lending).

Example 6: Case: a slowdown · 4 marks · Case-basedHOTS / competency

Suppose the economy faces a slowdown with falling demand and rising unemployment. Recommend three monetary measures the RBI can take, explaining the direction of each. (4 marks)

Try it first, then show the solutionSolution

Lower repo/bank rate (credit cheaper).
Lower CRR/SLR (more lendable funds; bigger multiplier).
Buy securities through OMO (inject reserves).
Lower margin requirement / moral suasion to encourage lending (any three).

Answer: Any three: (1) lower the repo rate and bank rate so banks borrow cheaply and cut loan rates; (2) lower the CRR or SLR so banks have more funds to lend and the money multiplier rises; (3) buy government securities in the open market to inject reserves; (4) lower margin requirements or use moral suasion to encourage lending. Cheaper and more available credit raises borrowing, spending and aggregate demand.

Where students lose marks in Central Bank Functions and Instruments of Monetary Policy

The slips examiners see most often, and what to write instead.

Mistake: Selling securities to fight deflation
OMO direction reversed.
Wrong working
To increase money supply, RBI sells bonds.
Right working
To increase money supply, RBI buys bonds; it sells to reduce it.
Do this: RBI buys, money flies in.
Usually costs: 1 to 2 marks.
Mistake: Defining repo as RBI borrowing
Repo and reverse repo swapped.
Wrong working
Repo rate: rate at which RBI borrows from banks.
Right working
Repo rate: rate at which RBI lends to banks; reverse repo: RBI absorbs funds.
Do this: Repo = RBI gives.
Usually costs: 1 mark.
Mistake: Saying CRR is kept by banks with themselves
CRR and SLR confused.
Wrong working
CRR: liquid assets kept with the bank itself.
Right working
CRR: cash reserves with the RBI; SLR: liquid assets kept by the bank itself.
Do this: CRR with Central bank; SLR with Self.
Usually costs: 1 mark.
Mistake: Giving direction without the chain
Board answers need the mechanism.
Wrong working
Raise CRR to control inflation.
Right working
Raise CRR → lendable funds and multiplier fall → credit and demand fall → inflation eases.
Do this: Tool → credit → demand.
Usually costs: 1 mark per tool.

Exam tips

Monetary policy tools and RBI functions are the most-tagged Money and Banking items in the PYQ bank (about nine items, 35 marks across board and sample papers).
Always state the direction and the chain of effects for each tool.
Do not quote current repo or CRR values unless the question gives them; the syllabus tests the mechanism.
Demand for money (transaction and speculative motives) is out of the 2026-27 syllabus.

Practice questions on Central Bank Functions and Instruments of Monetary Policy

Write each answer on paper first. Open the hint only if you are stuck, and the answer only when you have finished.

Q1 · 1 mark · MCQBoard level
To increase money supply, the RBI should:
(a) raise the CRR
(b) sell government securities
(c) lower the repo rate
(d) raise the margin requirement
Hint
Cheaper credit.
Answer
(c) lower the repo rate
Q2 · 1 mark · MCQBoard level
Which of these is a qualitative instrument of credit control?
(a) Bank rate
(b) CRR
(c) Margin requirement
(d) Open market operations
Hint
Directs credit to uses.
Answer
(c) Margin requirement
Q3 · 3 marks · Short answerBoard level
Explain any three functions of the Reserve Bank of India. (3 marks)
Hint
B-G-B-C-C.
Answer
Any three: (1) Bank of issue: sole authority to issue currency. (2) Government's bank: banker to the government. (3) Banker's bank and lender of last resort: banks keep reserves with it and it lends to them at all times. (4) Controller of credit through bank rate, repo, CRR, SLR, OMO. (5) Custodian of foreign exchange reserves.
Q4 · 2 marks · Short answerHarder board level
Distinguish between CRR and SLR. (2 marks)
Hint
Where kept, what form.
Answer
CRR is the percentage of deposits banks must keep as cash reserves with the central bank. SLR is the percentage of deposits banks must keep with themselves in liquid form such as cash, gold and approved securities.
Q5 · 3 marks · Short answerHarder board level
With a reserve ratio of 10%, banks receive fresh deposits of ₹6,000 crore. Find the maximum total deposits. What happens if the RBI cuts the ratio to 8%? (3 marks)
Hint
1 ÷ LRR.
Answer
At 10%: 6,000 ÷ 0.10 = ₹60,000 crore (multiplier 10). At 8%: 6,000 ÷ 0.08 = ₹75,000 crore (multiplier 12.5). Cutting the ratio raises credit capacity by ₹15,000 crore.
Q6 · 3 marks · Short answerHarder board level
How does an increase in the bank rate affect money supply? (3 marks)
Hint
Cost of borrowing from RBI.
Answer
The bank rate is the rate at which the RBI lends to commercial banks. A higher bank rate makes such borrowing costlier, so banks borrow less, their reserves fall and they raise their own lending rates. Borrowing and credit fall, so money supply decreases.
Q7 · 1 mark · Assertion-reasonHarder board level
Assertion (A): Purchase of government securities by the RBI increases money supply.
Reason (R): The RBI's payment for the securities adds to the reserves of commercial banks.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.
Hint
Reserves → credit.
Answer
(a) Both A and R are true and R is the correct explanation of A.
Q8 · 2 marks · Short answerHarder board level
Distinguish between outright open market operations and repo operations. (2 marks)
Hint
Permanent vs temporary.
Answer
Outright OMOs are permanent: the RBI buys or sells securities with no promise to reverse the deal, so the injection or absorption of money is permanent. In repo operations, the purchase agreement specifies the date and price of resale, so the injection is temporary.
Q9 · 3 marks · Short answerHOTS / competency
Suppose inflation is high but the government also wants banks to keep lending to farmers. Suggest a combination of quantitative and qualitative measures the RBI could use. (3 marks)
Hint
General tightening plus selective support.
Answer
Quantitative measures to reduce overall credit: raise the repo/bank rate, raise CRR or SLR, or sell securities. Qualitative measures to protect priority lending: use moral suasion to persuade banks to keep lending to agriculture, and raise margin requirements on loans against securities for speculative uses rather than for farm credit. This tightens credit overall while directing it towards desired uses.
Q10 · 3 marks · Short answerHOTS / competency
A student argues, 'If the RBI wants to cut inflation, it should just print less currency; the other tools are unnecessary.' Evaluate. (3 marks)
Hint
Money supply includes deposits created by banks.
Answer
Incomplete. Money supply includes demand deposits created by commercial banks, which can be many times their reserves through the money multiplier. Even with currency unchanged, banks can expand credit. So the RBI must also influence bank lending through repo and bank rates, CRR and SLR, open market operations and qualitative tools.

Test your recall

Answer in your head or on paper first, then open the card. Pulling an answer out of memory makes it stick far better than re-reading.

1.When was the RBI set up?Show answer
1935.
2.What is the repo rate?Show answer
The rate at which the RBI lends to commercial banks through repurchase agreements.
3.OMO to reduce money supply?Show answer
Sell government securities.
4.Money multiplier if CRR is 20%?Show answer
5.
5.Name two qualitative tools.Show answer
Margin requirement and moral suasion.
6.Which RBI role is 'lender of last resort'?Show answer
Banker's bank: lending to banks at all times.

Central Bank Functions and Instruments of Monetary Policy: frequently asked questions

What are the instruments of monetary policy in Class 12?

Quantitative: bank rate, repo rate, reverse repo rate, CRR, SLR and open market operations. Qualitative: margin requirement and moral suasion.

What are the functions of the central bank?

Issuing currency, acting as banker to the government and to banks (lender of last resort), controlling credit and keeping foreign exchange reserves.

How does the RBI control inflation?

By raising the repo, reverse repo and bank rates, raising CRR and SLR, selling securities in the open market and raising margin requirements, all of which reduce credit and demand.

What is the difference between repo and reverse repo?

In a repo the RBI lends to banks; in a reverse repo it absorbs funds from banks.