If d is a positive integer, is d^(1/2) greater than 15?

Taking Numbers would help.

Statement 1: d is divisible by 25

say d = 25; then d is divisible by 25, now \(\sqrt{25}\) = 5; it is less than 15
say d = 625; then d is divisible by 25, now \(\sqrt{625}\) = 25; it is greater than 15

Not sufficient.

Statement 1: d is divisible by 40

say d = 40; then d is divisible by 40, now \(\sqrt{40}\) = 2 * roughly (3.5), it is certainly less than 15
say d = 400; then d is divisible by 40, now \(\sqrt{400}\) = 20; it is greater than 15

Not sufficient.

Combining Statement 1 and 2: d is divisible by 40 and 25 both

Least value of such number would be 200 (LCM of 40 and 25).

say d = 200; then d is divisible by 40 and 25, now \(\sqrt{200}\) = 10 * 1.414, it is certainly less than 15
say d = 400; then d is divisible by 40 and 25, now \(\sqrt{400}\) = 20; it is greater than 15

Not sufficient.

Answer: E

Question
Is D> 225?
St:1
d is divisible by 25.
When d=25 answer is no
When d=250 answer is yes
Not sufficient

St-2
d is divisible by 40.
When d=40 answer is no
When d=400 answer is yes
Not sufficient

Combine:
D is divisible by 25 and 40
LCM of 25 and 40 =200
When d=200 answer is no
When d=1000 answer is yes
Ans: E

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