Question 989668
I went through a solution process earlier, but then thought more about the description, and decided not to try to finish.


You "have"  pennies, nickels and dimes;
and then you have a description involving quarters.
What is the exact problem description, word-for-word?


NO PENNIES; QUARTERS INSTEAD.
q, d, n, quarters nickels dimes
{{{system(d=2q,n=q+2,0.25q+0.1d+0.05n=7.60)}}}


Multiply the money equation by {{{20}}}.
{{{5q+2d+n=152}}}
Substitute the other relationships described.
{{{5q+2(2q)+(q+2)=152}}}
Solve for q first ; and then go back to the other two relationships to evaluate d and n.