About Solving Proportions:

A proportion states that two ratios/rates are equal. We can check to see if we have a proportion by cross multiplying. When the cross products are equal, we know we have a proportion. We solve a proportion equation by cross multiplying and using our four - step method for solving equations.


Test Objectives
  • Demonstrate the ability to determine if two ratios/rates represent a proportion
  • Demonstrate the ability to solve a proportion equation
  • Demonstrate the ability to solve a proportion word problem
Solving Proportions Practice Test:

#1:

Instructions: Solve each equation.

a)

12  =    x
10 x - 3

b)

 -7p  =  -3
p + 4 10

#2:

Instructions: Solve each equation.

a)

k + 8  =  5k + 6
  12     4

#3:

Instructions: Solve each equation.

a)

  4  =      12
r - 3 11r - 1

#4:

Instructions: Solve each equation.

a)

 y - 10  =  -11
2y + 8  12

#5:

Instructions: Solve each equation.

a) If 7 gallons of gas cost $27.58, how much would it cost to fill a 40 gallon tank?


Written Solutions:

#1:

Solutions:

a) x = 18

b)

p  =  12
67

#2:

Solutions:

a)

k  =  -5
 7

#3:

Solutions:

a)

y  =  16
17

#4:

Solutions:

a) x = 4.1


#5:

Solutions:

a) It would cost $157.60 to fill a 40 gallon tank.