Question

Find the sum of the first 20 terms of the Arithmetic series 4+7+10+.....

Answer 1

Answer:

the correct answer is 1410

Answer 2

Answer:

650

Step-by-step explanation:

a=4

n=20

d=3

therefore, Sn=n/2{2a+(n-1)d}

S20= 20/2{2×4+(20-1)×3}

=10{8+19×3}

=10{8+57}

=10{65}

=650

HOPE THIS WILL HELP ☺️