Question

The 2nd and 7 th term of an ap are 10 and 45. Find the 10 th term .

Answer 1

nth term of an AP = a+(n-1)d

2nd term = a+(2-1)d = a+d = 10

7th term = a+(7-1)d = a+6d = 45

5d = 35

d = 7

a + 7 = 10

a = 3

10th term = a+(10-1)d = a+9d

= 3+9×7

= 66

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