Question 1096484
Let the number of $20 bills be x, then the number of $5 bills is x+8

Since, all the bills adds up to $215, {{{20*x+5*(x+8) = 215}}}

Solving the above equation, we get x = 7

Therefore, Number of $20 bills = x = 7 and Number of $5 bills = x+8 = 15