RAS question
A machine follows these rules in each step: Step 1: Multiply the largest number by 2. Step 2: Subtract 3 from the smallest number. Input: 5, 12, 8, 3 What is the output after Step 1 and Step 2 (one round)?
Correct answer: (A) 5, 24, 8, 0.
After one complete round of the machine rules on 5, 12, 8, 3, the output is 5, 24, 8, 0 because the largest number, 12, is multiplied by 2 and 3 is subtracted from the smallest number, 3.
Explanation
Apply the two rules in the given order. In the starting sequence 5, 12, 8, 3, the largest number is 12. Step 1 multiplies only 12 by 2, so 12 × 2 = 24 and the sequence becomes 5, 24, 8, 3. Step 2 applies to the smallest number in this updated sequence. That number is still 3, and subtracting 3 from it gives 0. The final output after one complete round is therefore 5, 24, 8, 0. The NCERT Journal of Indian Education discusses the role of problem-solving in mathematics learning; this question similarly requires each arithmetic rule to be applied in the stated order.
Why the other options are wrong
- (B) It applies Step 1 correctly by changing 12 to 24, but leaves the smallest number 3 unchanged instead of subtracting 3 from it.
- (C) It subtracts 3 from the smallest number correctly, but multiplies 5 instead of the largest number 12 in Step 1.
- (D) It performs Step 2 correctly by changing 3 to 0, but misses Step 1 because 12 should become 24.
Concept
This tests machine input-output reasoning with ordered arithmetic instructions. First identify the number to which a rule applies, then perform the stated operation exactly once. Such RAS questions assess attention to sequence, comparison and basic computation together.