4.50 is the total value. Explanation:
Let d = number of dimes and n = number of nickels.
If the number of dimes is 4 times the number of nickels, then:
d = 4n
Since ""Joey has 10 nickels**,
n = 10
To evaluate the number of dimes, substitute n = 10 into,
d = 4n
d = 4(10)
d = 40 dimes
We set up an equation to reflect the monetary values as follows,
.10d + .05n = "total value"
Substitute d = 40 and Joey's n=10 nickels into the equation.
.10(40) + .05(10) = 4.00 + 0.50 = $4.50 is the total value.