Question

6)What is the sum of the first six terms of an AP whose first term is 3 and the sixth term is 27?


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Answer 1

Step-by-step explanation:

Answer: a =3.

an=27.

an=n/2(a+an).

=6/2(3+27).

=3(30).

=90

Therefore, the sum of first six terms of an AP is 90.

Answer 2

Given:

Terms of AP = first six

First term of the AP = 3

Sixth term of the AP = 27

To find:

The sum of the first six terms of the AP

Solution:

Since a =3. and an=27.

Using the formula of AP -

an = n/2 (a+an)

Substituting the values -

= 6/2 ( 3 + 27)

= 3 ( 3 + 27 )

=3 ( 30)

= 3 × 30.

= 90

Answer: The sum of the first six terms of the AP is 90.