Question

If 2+4+6+8+..+n ÷ 1+3+5+7+..+n=20÷19 Find n​

Answer 1

First take another variable to solve it then solve it easily...

Answer 2

2+4+6+8+...+n=n/2(2+n)

1+3+5+7+...+n=n/2(1+n)

n=18