Question

If $$a_1, a_2, a_3, ......, a_n$$ is a G.P. having common ratio r and k is a natural number such that $$3 < k < n$$, then r is equal to ______.

Options

• $$\frac{a_k}{a_1}$$

• $$\frac{a_1}{a_2}$$

• $$\frac{a_k}{a_{n-3}}$$

• $$\frac{a_{k-1}}{a_{k-2}}$$

Answer 1

If $$a_1, a_2, a_3, ......, a_n$$ is a G.P. having common ratio r and k is a natural number such that $$3 < k < n$$, then r is equal to `underlinebb((a_(k - 1))/(a_(k - 2))`.

Explanation: 

The common ratio is the ratio of any term to the preceding term. Hence, $$r = \frac{a_{k - 1}}{a_{k - 2}}$$.