Question

if the sum of frist 6 terms of an AP is 36 and that of the frist sixteen terms is 256 . find the sum of frist 10 terms.​

Answer 1

Answer:

If the sum of first 6 terms of an AP is 36 and that of the first 16 terms is 256

If sum of first 6 terms of an AP is 36 and that of the first 16 terms is 256 , then find the sum of first 10 terms. Solution : Let a d be the first term and common difference, respectively of an AP. Hence, the required sum of first 10 terms is 100.

Step-by-step explanation:

Answer 2

Answer:

110

Step-by-step explanation:

S6 = 36

6/2( 2a + 5d) = 36

2a + 5d = 12

2a = 12 - 5d.................................. (1)

Now, S16 = 256

256 = 16/2( 2a +15d )

2a +15d = 32

12 - 5d +15d = 32                                   (by 1)

d = 2

a = 2

S10 = 10/2 ( 2*2 + 9*2 )

110

ANSWER IS 110