Subba Rao started work in 1995 at an annual salary of ₹5000 and received an increment of ₹200 each year. In which year did his income reach ₹7000?

Starting salary = ₹5000

Increment each year = ₹200

₹5000, ₹5200, ₹5400, …………, ₹7000.

The above list of numbers is an A.P. with first term (a) = ₹5000 and common difference (d) = ₹200.

Let it take n years to reach ₹7000.

By formula,

⇒ a_n = a + (n - 1)d

⇒ 7000 = 5000 + 200(n - 1)

⇒ 7000 - 5000 = 200(n - 1)

⇒ 2000 = 200(n - 1)

⇒ n - 1 = $\dfrac{2000}{200}$

⇒ n - 1 = 10

⇒ n = 10 + 1 = 11.

Hence, in 11th year Subba Rao's income will reach ₹ 7000.