Question

The

Sum of
13 terms of an AP is 420.
what is it's 7th term​

Answer 1

Answer:

520

Let the first term be a and common difference is d,

a+(7−1)d=40

a+6d=40

Now the sum of 13 term's is

2/13 (2a+12d)= 13/2. 2.40=520

Step-by-step explanation:

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