Find the sum `7/5+5/7`

Find the sum 3/2-5/6+7/(18)-9/(54)+...oodot

Find the sum 3/2-5/6+7/(18)-9/(54)+oodot

Find the sum: 5/(12)+7/(16)

Find the sum: 5/9+\ 6+1 5/7

Find the sum to 25 terms of the A.P. 5, 7, 9, 11, …

Find the sum: 4(3)/(5)+2(7)/(8)

Find the sum 5^(2)+ 6^(2) + 7^(2) + ... + 20^(2) .

Find the sum 3(1)/(5)+4(3)/(5)+7(2)/(5)

Find the sum of 7 terms of the sequence (1/5+2/(5^2)+3/(5^3)),\ (1/(5^4)+2/(5^5)+3/(5^6)),\ (1/(5^7)+2/(5^8)+3/(5^9)),\ ,

Find the sum of n terms of the series 1.3.5.+3.5..7+5.7.9+...