Find the sum (-7)+(-9)+4+6

Find the sum : (a) (-7)+(-9)+4+16 (b) (37)+(-2)+(-65)+(-8)

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

Find the sum (-4/9 + (-5)/12 + 1/18)

Find the sum:  (i) 5/6+3+3/4 (ii) 2 3/5+4 7/(10)+2 4/(15)

Evaluate the sum: 2/(7)+6/(9)

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

Re- arrange suitably and find the sum: (-4)/7+7/6+2/7+\ 3+\ (-11)/6

Find the sum to n terms of the series (1)/(1*3*5*7*9)+(1)/(3*5*7*9*11)+(1)/(5*7*9*11*13)+"......" . Also, find the sum to infinty terms.

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

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