Question

In an AP a=5, d=3 ,an=50 find n and sn​

Answer 1

Step-by-step explanation:

An = a+ ( n-1) d

50 = 5+(n-1)3

50-5=3n-3

45+3=3n

n=16

Sn=n/2(a+An)

=8(5+50)

=8(55)

Sn =440

HOPE IT WOULD HELP U....

Answer 2

An = a + (n-1)d

==> 50 = 5 + (n-1) 3

==> 50-5 = (n-1)3

==> 45/3 = n-1

==> 15 = n-1

==> 16 = n

sum formula = n/2 (2a+(n-1)d

===> 16/2 [ 2(5) + (16-1)3 ]

===> 8 [ 10 + 45]

===> 8 [ 55]

===> 440