For a school fund raising project, aiden and jacob collected money in the
ratio 3.5 : 6.8. jacob collected $115.50 more than aiden. find the total
amount of money they collected. plz solve for me i got no time.

X=amount of money collected by Aiden.
y=amount of money collected by Jacob
x+y=total amount of money collected.

We can suggest the next system of equations:
x/y=3.5/6.8      ⇒x=3.5y/6.8
y=x+115.5

We solve this system of equations:
y=(3.5y/6.8) + 115.5
lower common multiple:
6.8y=3.5y+785.4
6.8y-3.5y=785.4
3.3y=785.4
y=785.4/3.3
y=238

x=3.5y/6.8=3.5(238)/6.8=122.5

Now we know that Aiden collected  $122.5 and Jacob collected $238.
Therefore:
Total amount collected=$122.5+$238=$360.5

The total amount collected was $360.5 

20000 as first it increases by 2500 then by 5000 so next it will increase by 10000