Question
Joe has 120 coins consisting of dimes and quarters with a value of $19.05. how many dimes and quarters does Joe have?
Answers
PsyDAG
Q = 120 - D
.25Q + .10D = 19.05
Substitute 120-D for Q in the second equation and solve for D. Insert that value into the first equation to solve for Q. Check by putting both values into the second equation.
.25Q + .10D = 19.05
Substitute 120-D for Q in the second equation and solve for D. Insert that value into the first equation to solve for Q. Check by putting both values into the second equation.