Question 5024
Let D = # of dimes ($0.10)
Let N = # of nickels ($0.05)

There are 5 time as many dimes as nickels, so: D = 5N Substitute this into the eqation below.
The total value of the coins is, so: ($0.10)D + ($0.05)N = $4.40

Now you have two equations and two unknowns.  You can solve the problem.

($0.10)(5N) + ($0.05)N = $4.40  Simplify.
($0.50)N + ($0.05)N = $4.40
($0.55)N = $4.40  Divide both sides by ($0.55)
N = 8  There are 8 nickels.
D = 5N
D = 5(8)
D = 40 There are 40 dimes.

Check:
($0.05)(8) + $).10)(40) = $0.40 + $4.00 = $4.40