QUESTION

CSAT

Medium

Maths

Prelims 2025

A question is given followed by two Statements 1 and 2. Consider the Question and the Statements and mark the correct option.

Question: Let P, Q, R, S be distinct non zero digits. If PP×PQ=RRSSPP \times PQ = RRSS, where P3P \le 3 and Q4Q \le 4, then what is Q equal to?

Statement-1: R=1R = 1. Statement-2: S=2S = 2.

Which one of the following is correct in respect of the above Question and the Statements?

Select an option to attempt

Explanation

PP is a two-digit number with the same digits: 11P11P. Similarly, PQ is the two-digit number: (10P+Q)(10P + Q). RRSS is a four-digit number with first two digits R and last two digits S and S.

Given: PP×PQ=RRSSPP \times PQ = RRSS (11P)×(10P+Q)=RRSS\Rightarrow (11P) \times (10P + Q) = RRSS

Step 2: Since P3P \le 3 and Q4Q \le 4, test values for P=1,2,3P = 1, 2, 3 and Q=1Q = 1 to 44.

Check P=3P = 3: PP=33PP = 33

Now compute 33×(30+Q)33 \times (30 + Q): Q=133×31=1023Q = 1 \rightarrow 33 \times 31 = 1023 (not of form RRSS) Q=233×32=1056Q = 2 \rightarrow 33 \times 32 = 1056 (not RRSS) Q=333×33=1089Q = 3 \rightarrow 33 \times 33 = 1089 (not RRSS) Q=433×34=1122Q = 4 \rightarrow 33 \times 34 = 1122 (this is RRSS form)

So: RRSS=1122R=1RRSS = 1122 \rightarrow R = 1 and S=2S = 2, and Q=4Q = 4.

Step 3: Did we need the statements? We derived the solution directly using the main condition.
The statements (R=1R = 1 and S=2S = 2) merely confirm what we already found.

Therefore, the question can be solved without using either statement.

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