SOLUTION: solve the following using a system of equations; Rod has 40 coins, all dimes and quarters, worth $7.60. How many dimes and how many quarters does he have?

Question 381914: solve the following using a system of equations;
Rod has 40 coins, all dimes and quarters, worth $7.60. How many dimes and how many quarters does he have?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Rod has 40 coins, all dimes and quarters, worth $7.60. How many dimes and how many quarters does he have?
--------
Equations:
Quantity Eq. d + q = 40
Value Eq:: 10d+25q = 760
------------------------------
Multiply thru the Quantity equation by 10 to get:
10d + 10q = 10*40
-----
Subtract that from the Value Eq and solve for "q":
15q = 360
q = 24 (# of quarters)
-----
Substitute into d+q = 40 and solve for "d":
d + 24 = 40
d = 16 (# of dimes)
=========================
Cheers,
Stan H.
RELATED QUESTIONS
Rod has 40 coins, all dimes and quarters worth $ 7.60. How many dimes and how many... (answered by mtmorro)

Solve the following using system of equations A collection of dimes and nickels is... (answered by Alan3354)

Solve the following using a system of equations: Marcy has a total of 100 dimes and... (answered by josmiceli)

Rob has 40 coins, all dimes and quarters, worth $7.60. How many dimes and how many... (answered by Edwin McCravy,Alan3354)

Rob has 40 coins, all dimes and quarters worth $3.60. How many quarters does she have. (answered by Boreal,ikleyn,Alan3354)

40 coins , nickel, dimes and quarters worth $4.05. 7 more nickels than dimes. How many... (answered by mananth)

Warren has 40 coins (all nickels, dimes, and quarters) worth $4.05. He has 7 more... (answered by stanbon)

Warren has 40 coins (all nickels, dimes, and quarters) worth $4.05. He has 7 more... (answered by nerdybill)

warren has 40 coins (all nickels, dimes, and quarters) worth 4.05. He has 7 more nicles... (answered by amoresroy)