Select the set in which the numbers are related in the same way as are the…
2025
Select the set in which the numbers are related in the same way as are the numbers of the following sets.
(NOTE: Operations should be performed on the whole numbers, without breaking down the numbers into their constituent digits. E.g. 13 - Operations on 13 such as adding to/subtracting from/multiplying with 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)
7 − 3 − 20
4 − 5 − 18
- A.
4 − 7 − 22
- B.
5 − 3 − 18
- C.
16 − 3 − 36
- D.
6 − 8 − 26
Attempted by 3 students.
Show answer & explanation
Correct answer: A
Concept
In a number-set analogy question, one fixed arithmetic rule connects the three numbers within each given reference set. Once that rule is identified from the reference sets, it must hold exactly, without exception, for the number set chosen as the answer.
Application
In 7 − 3 − 20: the sum of the first two numbers is 7 + 3 = 10, and twice this sum is 10 × 2 = 20, which equals the third number.
In 4 − 5 − 18: the sum of the first two numbers is 4 + 5 = 9, and twice this sum is 9 × 2 = 18, which equals the third number. Both reference sets follow the same rule: third number = 2 × (sum of the first two numbers).
Applying this rule to 4 − 7 − 22: 2 × (4 + 7) = 2 × 11 = 22, which matches the third number exactly.
Applying the same rule to 5 − 3 − 18: 2 × (5 + 3) = 16, which does not match 18.
Applying the same rule to 16 − 3 − 36: 2 × (16 + 3) = 38, which does not match 36.
Applying the same rule to 6 − 8 − 26: 2 × (6 + 8) = 28, which does not match 26.
Cross-check
As an independent check, dividing the third number by 2 should return the sum of the first two numbers: 20 ÷ 2 = 10 = 7 + 3; 18 ÷ 2 = 9 = 4 + 5; and for 4 − 7 − 22, 22 ÷ 2 = 11 = 4 + 7. This confirms the rule is applied consistently across the reference sets and the chosen set.
Hence, the set "4 − 7 − 22" follows the same relation as the two reference sets.