An arithmetic progression has first term 11 and fourth term 32. The sum of the first nine terms is

AityHolycity

6 years ago

its 351 because. .
....

1st term a = 11, 4th term = 32

nth term = a + (n - 1)d

4th term = 11 = (4 - 1)d

= 11 + 3d

= 32

3d = 21

d = 7

sn = n(2a + (n - 1)d)

sn = 92(2 \times 11) + (9 - 1)7

92(22 + 56) = 92 x 78

= 351

eserogs

1 year ago

ddgyt

Kidfuryxl1

1 year ago

i dont think is solve able