Question

What is the sum of first six term of an A.P whose first term is 3and the sixth term is 27

Answer 1

Answer:

a =3

an=27

an=n/2(a+an)

=6/2(3+27)

=3(30)

=90

sum of first six terms of AP is 90

Answer 2

Answer:

90

Step-by-step explanation:

GIVEN:A=3,A6=27

TO FIND:S6 =?

SOLUTION:

S6=n/2(a+a6)

S6=6/2 (3+27)

S6=3(30)

s6=90