Question 853275
1)
{{{sum(6.6n-5.4,n=0,4)}}}
=39
2)
{{{sum(6.6n-4.4,n=0,4)}}}
=44
3)
{{{sum(4.4n-6.6,n=1,5)}}}
=33
4)
{{{sum(6.6n-4.4,n=1,5)}}} 
=77
 #4 is correct

2.2+8.8+15.4+22+28.6=77