Select the pair of numbers that has the same relationship as 11 : 124.

13 : 172Correct answerYour answer12 : 146Correct answerYour answer14 : 193Correct answerYour answer9 : 90Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer A

Correct answer: A

$11^2 = 121$ and $124 = 121 + 3$ : square the first number and add 3.
$13^2 + 3 = 169 + 3 = 172$ , so 13 : 172 matches.
$12^2 + 3 = 147$ , not 146; $14^2 + 3 = 199$ , not 193; $9^2 + 3 = 84$ , not 90.

Worth noting

Every pair is 'a square plus or minus a little', so each one must be checked exactly: 12 : 146 is $12^2 + 2$ and 14 : 193 is $14^2 - 3$ .

Ten questions from Analogies and Classification, at your own pace.

Ten questions from Analogies and Classification, at your own pace.

Explanation