Coin Problems
Students will use Guess and
Check Chart and Algebra to solve
Coin Word Problems
What are coins worth?
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A penny
A nickel
A dime
A quarter
.01
.05
.10
.25
5(.01) = .05
What are 5
pennies worth?
What are 7
nickels worth?
7(.05) = .35
What are 8
dimes worth?
8(.10) = .80
What are 9
quarters worth? 9(.25) = 2.25
Setting Up A Guess & Check Chart
 Set up a column for each coin in
problem
 The last column should be for Total
Amount of Money
 Bill has four times as many quarters as
dimes. He has $2.20 altogether. How many
of each coin does he have?
D (?) Q (4D)
Total (2.20)
Key Phrase: Four times as many quarters as dimes
This tells us that if we know: how many dimes
We can figure out: how many quarters
So our guess column will be the Dime column
 Bill has four times as many quarters as
dimes. He has $2.20 altogether. How many
of each coin does he have?
The guess column
D (?) Q (4D)
5
20
Total (2.20)
5(.10) + 20(.25)
.50 + 5.00 = 5.50
 Bill has four times as many quarters as
dimes. He has $2.20 altogether. How many
of each coin does he have?
D (?) Q (4D)
5
20
Total (2.20)
5(.10) + 20(.25)
.50 + 5.00 = 5.50
3
12
3(.10) + 12(.25)
.30 + 3.00 = 3.30
2
8
2(.10) + 8(.25)
.20 + 2.00 = 2.20
Bill has 2
dimes and 8
quarters
We found the total!!!
 Bill has four times as many quarters as
dimes. He has $2.20 altogether. How many
of each coin does he have?
To convert to Algebraic Equation:
The guess column becomes x!
D (?) Q (4D)
2
8
X
4x
Total (2.20)
2(.10) + 8(.25)
.20 + 2.00 = 2.20
X(.10) + 4x(.25) = 2.20
The Total Column becomes the equation!
Using Algebra to Solve
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
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

STEPS
Define variables
Write an equation
Solve equation
Answer question !
 Bill has four times as many quarters as
dimes. He has $2.20 altogether. How many
of each coin does he have?
The guess column becomes x!
D (?) Q (4D)
X
4x
Total (2.20)
x(.10) + 4x(.25) = 2.20
The Total Column becomes the equation!
Let x = # dimes
x(.10) + 4x(.25) = 2.20 Answer:
Let 4x = # quarters .10x + 1.00x = 2.20
1.10x = 2.20
Bill has 2 dimes
and 8 quarters.
x = 2 Hint: Keep 2 decimal places so
your numbers look like money
Paul has twice as many dimes as pennies and
3 times as many nickels as pennies. He has
$1.80. How many of each type of coin?
 Set up chart !!!
Start Guessing!
If we know how many
pennies, we can figure
nickels & dimes!
P (?) N (3P) D (2P) Total (1.80)
Paul has twice as many dimes as pennies and
3 times as many nickels as pennies. He has
$1.80. How many of each type of coin?
P (?) N (3P) D (2P) Total (1.80)
2(.01) + 6(.05) +4(.10)
2
6
4
.02+.30+.40=.72
4
12
8
4(.01) + 12(.05)+8(.10)
.04+.60+.80=1.44
5
15
10
5(.01) + 15(.05) + 10(.10)
.05+.75+1.00=1.80
Paul had 5 pennies, 15 nickels, and 10
dimes.
Paul has twice as many dimes as pennies and
3 times as many nickels as pennies. He has
$1.80. How many of each type of coin?
P (?) N (3P) D (2P) Total (1.80)
5(.01) + 15(.05) + 10(.10)
5
15
10
.05+.75+1.00=1.80
X
3x
Let x = #pennies
Let 3x=#nickels
Let 2x=#dimes
2x
X(.01)+3x(.05)+2x(.10)=1.80
X(.01)+3x(.05)+2x(.10) = 1.80
.01x+.15x+.20x=1.80
.36x=1.80
X=5
Paul had 5 pennies,
15 nickels and 10
dimes.
Wrapping It Up-Coin Problems
 How do you label
your Guess & Check
chart?
 How do you decide
which column is x?
 What is the most
important thing you
will do when solving
a word problem?
 All coins and Total
Amount
 The guess column
 Answer the
question!!!!!!