Question 881930
Sheryl saves her dimes and quarters. She currently has a total of 24 coins, all of which are dimes and quarters.
 a. Write an equation that gives the total amount of money M (in dollars) as a function of the number of dimes d she has.
------
M = 0.10d + 0.25q
d + q = 24
----
q = 24-d
-----
Ans: M = 0.10d + 0.25(24-d)
M = (0.10-0.25)d + 6
M = -0.15d + 6
===============================================================

 b. Show how you can use the distributive property to find the total amount of money she has if she has 13 dimes.
M = 13d = 10d+3d
===============================================================

 c. If Sheryl's 24 coins have a total value of $4.80, how many dimes and quarters does she have? Use a table of values and explain how you found your answer.
Value Eq:: 10d + 25q = 480 cents
Quantity::  d + q = 24
-----------------------------
Substitute to solve for "d":
10d + 25(24-d) = 480
10d + 600 - 25d = 480
-15d = -200
Note:: solution is not a whole number
=======================================
Cheers,
Stan H.
===================