The income of a person is ₹ 300, 000 in the first year and he receives an increase of ₹ 10, 000 to his income per year for the next 19 years. Find the total amount, he received in 20 years.

Given: The income of a person is ₹ 300, 000 in the first year


and he receives an increase of ₹ 10, 000 to his income per year for the next 19 years.


To find: the total amount he received in 20 years i.e. S20


According to question:


a = 300000, d = 10000 and n = 20


Formula used:



where a is first term, d is common difference and n is number of terms in an A.P.


Therefore,





S20 = 10(790000)


S20 = 7900000


Hence, the total amount he received at the end of 20 years is Rs. 790000


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