Question

Find the sum of the AP:14, 21, 28, …, 168

Answer 1

Answer:

an=a+(n-1)d

168=14+(n-1)7

168-14=7n-7

154+7=7n

161/7=n

23=n

sn=n/2(a+an)

sn=23/2(14+168)

sn=23(91)

sn=2093

Hope, it helps you!!!!!