terminating decimal

[mehrasa]

is the r/s^2 terminating decimal?
1) s=225
2) r=81

[sl750]

s=225 has a factor of 3, so s^2 will have two factors of 3. We have a possibility of a recurring decimal. Insufficient

r=81. Insufficient, as we don't know what the value of s is

Statement 1 and 2

3^4/(5^2*3^2) = 3^2/25 = Terminating decimal. Sufficient

[Anurag@Gurome]

is the r/s^2 terminating decimal?
1) s=225
2) r=81

(1) r/s² = r/(225)² = r/(9^2 * 5^4)
We cannot say whether r/s² will be terminating in this case; NOT sufficient.

(2) r = 81 is obviously NOT sufficient.

Combining (1) and (2), r/s² = 9²/(9^2 * 5^4) = 1/(5^4), which is definitely a terminating decimal; SUFFICIENT.

The correct answer is C.