Question

Which number is rational?
/2
10
O
16

Answer 1

16

Explanation:

Square root of 2 is irrational. This has been proven by the Pythagoreans (there is a simple proof of that).

pi is also known to be irrational although the proof is a bit more demanding.

Square root of 10 can be written as a product of square root of 5 and square root of 2, which themselves are irrational. Any product involving an irrational number is irrational

Square root of 16 = 4. 4 can be written as a fraction 4/1, or 8/2, 16/4, etc. and therefore is rational by definition.