Question

8th term of an AP is 36 and 10th term is 28. What is its 11th term

Answer 1

Step-by-step explanation:

a8 = 36

a10= 28

a11 =?

a(n) = a + (n-1)d

36 = a + (8-1)d

36 = a + 7d .....(1)

28 = a + (10-1)d

28 = a + 9d .....(2)

(1) - (2)

36 = a + 7d

(-)

28 = a + 9d

8 = -2d

d = -4

28 = a + 9(-4)

28 = a - 36

a = 64

a11 = 64 + 10(-4)

a11 = 24