Question

for an AP it is given that the first term is equal to 5 common difference is equals to 3 and the end term a n is equals to 50 find the n and sum of first n terms of the AP​

Answer 1

Answer

an=50

a=5

d=3

an=a+(n-1)d

50=5+(n-1)3

50-5=3n-3

45+3=3n

48/3=n

n=16

Sn=n/2[2a+(n-1)d]

Sn=16/2[2×5+(16-1)3]

Sn=8[10+(15)3]

Sn=8[10+45]

Sn=8×61

Sn=440

Step-by-step explanation: