a. 1 : $\frac{1}{10}$ = 10
So 1 is greater than $\frac{1}{10}$ 10 times
b. $\frac{1}{10} : $\frac{1}{100} = 10
So $\frac{1}{10} is greater than $\frac{1}{100} 10 times
c. $\frac{1}{100} : $\frac{1}{1000} = 10
So $\frac{1}{100} is greater than $\frac{1}{1000} 10 times