Q24 of 167 Page 19

Find the sum of n terms of the A.P. whose kth terms is 5k + 1

given an AP whose kth term is 5k + 1

To find: the sum of n terms of an AP whose kth term is 5k + 1

So substituting k = 1 to get the first term a₁ = 6

Substituting k = 2 to get the second term a₂ = 11

d = a₂ - a₁ = 5

we know that the sum of AP is given by the formula:

substituting the values in the above equation

If the 12th term of an A.P. is - 13 and the sum of the first 4 terms is 24, what is the sum of the first 10 terms?

If the 5th and 12th terms of an A.P. are 30 and 65 respectively, what is the sum of the first 20 terms?

Find the sum of all two digit numbers which when divided by 4, yields 1 as the remainder.

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