Question

Which number produces an irrational number when multiplied by -1.25

A. 3/4
B. 5.21
C.-0.454545
D. sqaure root 17

Answer 1

D. Square root of 17

Answer 2

Answer: Option 'D' is correct.

Explanation:

When a rational number is multiplied by rational number , it gives rational number only.

When an irrational number is multiplied by rational number, it gives irrational number always.

Since we need to produce an irrational number .

A. 3/4 is a rational number if we multiply by -1.25 it will remain a rational number.

B.
`5.21=(521)/(100)` is a rational number if we multiply by -1.25 it will still remain a rational number.

C.
`-0.454545=-0.\bar{45}=(-45)/(99)` is a rational number if we multiply by -1.25 it will still remain a rational number.

D. square root 17 = √17 is an irrational number if we multiply by -1.25 , it still remain irrational number.

So, Option 'D' is correct.