Word Problem Practice
Functions
1. TRANSPORTATION The cost of riding in a cab is
$5.00 plus $0 75 per mile. The equation that
represents this relation is 0.75x + 3, where is the
number of miles traveled and is the cost of the trip
Look at the graph of the equation and determine
whether the relation is a function
4. TRAVEL The cost for each car entering President
George Bush Turnpike at Beltline road is $0.75. The
equation that represents this relation is y=0.75x,
where r is the number of cars entering the turnpike at
Beltline Road and y is the amount of money collected
Determine if this relation is a function. Explain
Cost (5)
5. CONSUMER CHOICES Aisha just received a $40
paycheck from her new job. She spends some of it
buying music online and saves the rest in a bank
account. Her savings is given by f(x) = 40 - 1.25x,
where r is the number of songs she downloads at
$1.25 per song
1
2
3
9 10%
4 5 6 7 8
Distance (miles)
a. Graph the function.
2. TEXT MESSAGING Many cell phones have a text
messaging option in addition to regular cell phone
service. The function for the monthly cost of text
messaging service from Noline Wireless Company is
RY) = 0.10x + 2. where r is the number of text
messages that are sent. Find R10) and R30), the cost
of 10 text messages in a month and the cost of 30 text
messages in a month
b. Find (3). 118). and 1( 36). What do these values
represent?
3. GEOMETRY The area for any square is given by the
function v=x? where r is the length of a side of the
square and v is the area of the square. Write the
equation in function notation and find the area of a
square with a side length of 3.5 inches.
c. How many songs can Aisha buy if she wants to
save $30?
Glencoe Algebra 1
46
Chapter