Question

29. Find the 31st term of an A.P., whose 11th term is 88 and 16th term is 73. Which term of this
series will be the 1st negative term ?​

Answer 1

Answer:

→Given that,

a¹¹ = 38

a¹⁶ = 73

→We know that,

an = a + (n-1)d

a¹¹ = a+(11−1)d

38 = a+10d (i)

→Similarly,

a¹⁶ = (16-1)d

73 = a + 15d (ii)

→On subtracting (i) from (ii), we get

35=5d

d=7

→From equation (i),

38=a+(10)(7)

38−70=a

a = (-32)