Question

if for an a.p. the first term is 3 and the common difference is 4 then find s 10
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Answer 1

S₁₀ = 210

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Solution :- Given first term 'a' = 3

common diffrence 'd' = 4

number of term 'n' = 10

we have to find S₁₀

• As we know that , Sₙ = n/2[2a+(n-1)d]

1. S₁₀ = 10/2[ 2×3 + (10-1)*4 ]

• S₁₀ = 5× (6+36)

• S₁₀= 5× 42

• » S₁₀= 210Answer

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Answer 2

Answer:

• Sum of 10 terms is 210.

Step-by-step explanation:

Given:-

• First term is 3.
• Common difference is 4.

To find:-

• Sum of 10 terms of A.P.

Solution:-

We know that

$\boxed{ \sf s_{n} = \cfrac{n}{2}(2a + (n + 1)d) }$

In which,

• n, a and d are number of terms, First term and common difference respectively.

n = 10

a = 3

d = 4

Put the values in formula

➝ S₁₀ = 10/2 [ 2 × 3 + (10 - 1) × 4]

➝ S₁₀ = 5 [ 6 + (9) × 4]

➝ S₁₀ = 5 [6 + 36]

➝ S₁₀ = 5 × 42

➝ S₁₀ = 210.

Therefore

Sum of 10 terms of A.P is 210.