Question 538769
You have 83 coins which consist of nickels and dimes that equal $6.95 how many of each do you have? 
:
The no. of coins equation:
n + d = 83
n = (83-d); use the form for substitution
:
The value equation
.05n + .10d = 6.95
replace n with (83-d)
.05(83-d) + .10d = 6.95
4.15 - .05d + .10d = 6.95
.05d = 6.95 - 4.15
.05d = 2.80
d = {{{2.8/.05}}}
d = 56 dimes
:
You can find the number of nickels, check your solutions in the value equation