find the sum of `n` terms of the series `(4-1/n)+(4-2/n)+(4-3/n)+...........`

Find the sum of n terms of the series 1+4+10+20+35+…

Find the sum to n terms of the series (1.2.3) + (2.3.4) + (3.4.5) ...

Find the sum of n terms \ of the series: 1/(1. 2)+1/(2. 3)+1/(3. 4)+...............+1/(n.(n+1))

Find the sum of n terms \ of the series: 1/(1. 2)+1/(2. 3)+1/(3. 4)+...............+1/(n.(n+1))

Find the sum of first n terms and the sum of first 5 terms of the geometric series 1+ 2/3 +4/9 +............

Find the sum of first n terms and the sum of first 5 terms of the geometric series 1+ 2/3 +4/9 +............

Find the sum of first n terms and the sum of first 5 terms of the geometric series 1+ 2/3 +4/9 +............

Find the sum of first n terms and the sum of first 5 terms of the geometric series 1+ 2/3 +4/9 +............