let d = number of dimes and n = number of nickel.
We can now set up the following system of equations:_
10d + 5n = 310.................................(1)
n - d = 5
multiply second equation by -5:-
-5n + 5d = -25.....................................(3)
Adding (1) and (3) gives:_
15d = 285
d = 19 and so n = 19+5 = 24
So she has 19 dimes and 24 nickels Answer
