Find the sum :
`1+1.2+1.4+1.6+1.8+...` (upto 21 terms)

Find the sum : 1 1/8 - 2 3/4 + 6 2/3

Find sum of series 1.2+2.3+3.4.... upto n terms

Find the sum of the GP: (i) 1+3+9+27+... to 7 terms (ii) 1+sqrt(3)+3+3sqrt(3)+... to 10 terms (iii) 0.15+0.015+0.0015+... to 6 terms (iv) 1-1/2+1/4-1/8+... to 9 terms (v) sqrt(2)+1/sqrt(2)+1/(2sqrt(2))+... to 8 terms (vi) 2/9-1/3+1/2-3/4+... to 6 terms

The odd value of n for which 704 + 1/2 (704) + 1/4 (704) + ... upto n terms = 1984 - 1/2 (1984) + 1/4 ( 1984) - .... upto n terms is :

Find the sum of the grometric series 1+1/2+1/4+1/8+... to 12 terms.

The sum of the series: 1+(1)/(1+2)+(1)/(1+2+3)+.... upto 10 terms,is :

The sum of the series: 1+(1)/(1+2)+(1)/(1+2+3)+...... upto 10 terms is :

Find the sum of the series,1.3.4+5.7.89.11.12+...... upto n terms.

If alpha = 1^2 4^2 8^2 13^2 ........ upto 10 terms and beta = sum_(N=1)^(10) N^4 such that 4alpha - beta = 55 k 40 , then find k.

Find the sum of the series upto 10 terms: 4+8+12+....