Question

30^th term of the AP: 10, 7, 4, ……….. is 

(A) 97 

(B) 77 

(C) -77 

(D) -87

Answer 1

Answer is (C)

a = 10. d = 7 – 10 = -3, n = 30, a₃₀ =? 

a_n = a + (n – 1)d 

a₃₀ = 10 + (30 – 1)(-3) 

= 10 + 29(-3) 

= 10 – 87 

∴ a₃₀ = -77