Question

the first term of AP is 6 & common difference is 3 find S27 ​

Answer 1

Answer:

a=6

d=3

s27=?

s=n/2(2a+(n-1)d)

s27=27/2(2×6)+(27-1)3

s27=27/2×90

s27=1215

Answer 2

Given :-

• First term ( a ) = 6
• Common difference ( d ) = 3

We need to find :-

• S₂₇ = ?

Solution :-

As we know that ,

• Sn = n/2 [ 2a + ( n - 1 ) d ]

Where ,

• Sn is sum of first n terms = ?
• n is no. of terms = 27
• a is first term = 6
• d is common difference = 3

Substituting we have ,

➵ S₂₇ = 27/2 [ 2 ( 6 ) + ( 27 - 1 ) 3 ]

➵ S₂₇ = 27/2 [ 12 + 26(3) ]

➵ S₂₇ = 27/2 [ 12 + 78 ]

➵ S₂₇ = 27/2 [ 90 ]

➵ S₂₇ = 27 × 45

➵ S₂₇ = 1215

Hence , sum of first 27 terms ( S₂₇ ) is 1215