Question

The sum of first seven terms of an arithemetis sequrnce is 119 and the sum of 11th term is 275wjay is 4th term​

Answer 1

Question:-

The sum of first seven terms of an arithemetis sequrnce is 119 and the sum of 11th term is 275, what is the 4th term?

So, we have to find the 4th term of AP here with the help of given sum of first 7 and 11 terms of AP.

Given:-

• Sum of first 7 terms of an AP, S₇ = 119
• Sum of first 11 terms of the AP, S₁₁ = 275

Solution :-

As we know that,

Sₙ = n/2 × [ 2a + (n - 1)d ]

S₇ = 7/2 × [ 2a + (7 - 1)d ]

S₇ = 7/2 × [ 2a + 6d ]

119 = 7/2 × [ 2 ( a + 3d ) ]

119 = 7 ( a + 3d )

119/7 = a + 3d

17 = a + 3d ...eq-1

Now,

aₙ = a + (n - 1)d

a₄ = a + (4 - 1)d

a₄ = a + 3d ...eq-2

Hence, from eq-1 and eq-2,

Fourth term of AP is 17 ( a₄ = 17 ).

Answer 2

Answer:

the 4th term is 17 is the answer