Why is $7 \times 11 \times 13 + 13$ a composite number? Explain.

Which of the following is Bezout's identity?

Without actually performing the long division,find if $\frac{987}{10500}$ will have a terminating or non-terminating (repeating) decimal expansion. Give reasons for your answer.

According to Euclid's division lemma,for given positive integers $a$ and $7$,there exist unique non-negative integers $q$ and $r$ such that $a = 7q + r$; where..........

Without actually performing the long division,state whether the following rational number will have a terminating decimal expansion or a non-terminating repeating decimal expansion: $\frac{13}{3125}$.

Which of the following rational numbers has a non-terminating repeating decimal expansion? $(A)$ $\frac{17}{32}$,$(B)$ $\frac{17}{248}$,$(C)$ $\frac{17}{160}$