IAS 2020 — CSAT Maths

2020mcqeasy

What is the largest number among the following?

Official previous-year question

Verified 2 Aug 2026.

Options

A $\left( \frac{1}{2} \right)^{- 6}$
B $\left( \frac{1}{4} \right)^{- 3}$
C $\left( \frac{1}{3} \right)^{- 4}$
D $\left( \frac{1}{6} \right)^{- 2}$

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Solution

Correct Option (c)

To determine the largest number, each expression must be evaluated. For option (c), the expression is $\left( \frac{1}{3} \right)^{- 4}$ . Utilizing the property $a^{-n} = \frac{1}{a^n}$ or $\left( \frac{1}{x} \right)^{-n} = x^n$ , this simplifies to $3^4$ . Calculating $3^4$ yields $3 \times 3 \times 3 \times 3 = 81$ . This value represents the maximum among the given options.

Incorrect Options:

The other options evaluate as follows:

For option (a), $\left( \frac{1}{2} \right)^{- 6}$ simplifies to $2^6$ . Calculating $2^6$ gives $2 \times 2 \times 2 \times 2 \times 2 \times 2 = 64$ .
For option (b), $\left( \frac{1}{4} \right)^{- 3}$ simplifies to $4^3$ . Calculating $4^3$ gives $4 \times 4 \times 4 = 64$ .
For option (d), $\left( \frac{1}{6} \right)^{- 2}$ simplifies to $6^2$ . Calculating $6^2$ gives $6 \times 6 = 36$ .

Comparing the evaluated values (64, 64, 81, 36), it is evident that 81 is the largest number, making options (a), (b), and (d) incorrect because their values are smaller than 81.

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Solution

Correct Option (c)

Incorrect Options:

The other options evaluate as follows:

For option (a), $\left( \frac{1}{2} \right)^{- 6}$ simplifies to $2^6$ . Calculating $2^6$ gives $2 \times 2 \times 2 \times 2 \times 2 \times 2 = 64$ .
For option (b), $\left( \frac{1}{4} \right)^{- 3}$ simplifies to $4^3$ . Calculating $4^3$ gives $4 \times 4 \times 4 = 64$ .
For option (d), $\left( \frac{1}{6} \right)^{- 2}$ simplifies to $6^2$ . Calculating $6^2$ gives $6 \times 6 = 36$ .

Comparing the evaluated values (64, 64, 81, 36), it is evident that 81 is the largest number, making options (a), (b), and (d) incorrect because their values are smaller than 81.

IAS 2020 — CSAT Maths

Options

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Solution

Correct Option (c)

Incorrect Options:

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IAS 2020 — CSAT Maths

Options

Did you get this right?

Solution

Correct Option (c)

Incorrect Options:

Your note

IAS Maths in other years

More IAS Maths questions

Other CSAT topics for IAS

Comprehension

Reasoning

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