Question

Find the common difference of an AP whose first term is 4,the last term is 49
and the sum of all it's term is 265

Answer 1

)(Answer:

Step-by-step explanation:

a = 4

an = 49

sn = 265

    = n/2 (a+l)

    = n/2 (53)

265=n/2 (53)

n/2 = 265/53

     = 5

: n = 10

an = a+(n-1)d

49 = 4+ (5-1) d

49 = 4+4d

4d= 49-4

4d= 45

d= 45/4

=11.25