Question

The third and seventh terms of an ap are respectively -2 and 10 find the value of the first term and number of term which must be add to give sum of 410

Answer 1

Where is the answer

Answer 2

Where is the working

Answer 3

Am asking the same question

Answer 4

Tn = a + (n-1) d

so for example T3 = a + 2 d and T7 = a + 6 d
that gives you two linear equations to solve for a and d
then use the equation for sum of terms to find the n for sum of 410

Answer 5

If you do not understand what I said, Google:

Math is Fun arithmetic sequence

Answer 6

a+2d = -2

a+6d = 10
solve for a and d, and then you have
n/2 (2a+(n-1)d) = 410
Since you now know a and d, just use them to solve for n

Answer 7

I am not about to do it for you. It is pure plug and chug.