Expand and simplify the following:

Question

4
∑
i=1(i+3/i+4)
(1+3/1+4)+(2+3/2+4)+(3+3/3+4)+(4+3/4+4)
4/5+5/6+6/7+7/8
I am stuck here please help me.

Answer 1

Not certain what your issue is, in your google search window,
4/5+5/6+6/7+7/8=
3.36547619 is given as an approximate answer.

Answer 2

It gets a bit messy, but since the LCD is 5*6*7*4=840
4/5+5/6+6/7+7/8
= (4*168 + 5*140 + 6*120 + 7*105)/840 = 2827/840