(i) Denominator of is 80.
And,
80 = 245
Therefore, 80 has no other factors than 2 and 5.
Thus, is a terminating decimal.
(ii) Denominator of is 24.
And,
24 = 233
So, 24 has a prime factor 3, which is other than 2 and 5.
Thus, is not a terminating decimal.
(iii) Denominator of is 12.
And,
12 = 223
So, 12 has a prime factor 3, which is other than 2 and 5.
Thus, is not a terminating decimal.
(iv) Denominator of is 35.
And,
35 = 75
So, 35 has a prime factor 7, which is other than 2 and 5.
Thus, is not a terminating decimal.
(v) Denominator of is 125.
And,
125 = 53
Therefore, 125 has no other factors than 2 and 5.
Thus, is a terminating decimal.