One of the most important and exam oriented question from Chapter name- Arithmetic Progression

Class 10th

Chapter number- 9

Exercise :- 9.6

This type of question has been asked in previous years exams.

In this question we have been given an arithmetic progression. And we have to find out sum of this progression upto 10 terms.

CBSE DHANPAT RAI publication

CBSE Mathematics Class 10th

Question 1 ( i)

Given A.P. has first term(a) = 50,

Common difference(d) = 46 – 50 = – 4

and number of terms(n) = 10

So, Sum of A.P. = S

_{10}= n[2a + (n – 1)d] / 2= 10[2(50) + (10 – 1)(-4)]/2

= (10)(100 – 36)/2

= 320

Hence, the sum of the first 10 terms of A.P. is 320.