Question:
How many digits are there in the repeating block of digits in the decimal expansion of $\frac{17}{7} ?$
(a) 16
(b) 6
(c) 26
(d) 7
Solution:
$\because \frac{17}{7}=2 . \overline{428571}$
So, there are 6 digits in the repeating block of digits in the decimal expansion of $\frac{17}{7}$.
Hence, the correct option is (b).