Question

plz answer this question with detailed steps​

Answer 1

Answer:

answer is 36 of this sum

Answer 2

Answer:

35

Step-by-step explanation:

We know that the sum of n terms of arithematic progression is:

$S_{n} =\frac{n}{2}(2a+(n-1)d)$

Where:

n = Number of terms

a = First term

d = difference between the terms

∴ According to the question

$\frac{\frac{n}{2} (2(3)+(n-1)2)}{\frac{10}{2}(2(5)+(10-1)3)}=7$

⇒$\frac{2n(6+2n-2)}{20(10+27)}=7$

⇒$\frac{n(4+2n)}{10(37)} =7$

⇒$\frac{2n(2+n)}{10(37)}=7$

⇒$\frac{n(2+n)}{5(37)}=7$

⇒$n^{2} +n-1295=0$

Quadratic formula = $\frac{-b\pm\sqrt{b^2-4ac}}{2a}$ for the equation $ax^2+bx+c=0$

by applying the formula we get n = 35 and -37

∵ n cannot be negative

n = 35