You are buying balloons for an upcoming work party.

Question

The latex balloons are $.10 each and the mylar balloons are $.50 each. You need 125 balloons and you have $32.50 to spend. How many of each can you buy?

Answer 1

Hi Yarima, let L represent the latex balloons and M represent the mylar balloons. Then set up to equations representing the information you know.

 

Equation 1, number of balloons:

 

L + M = 125

 

Equation 2, cost of balloons:

 

.1L + .5M = 32.50

 

Solve:

 

   L  +    M  = 125

.1L  + .5M  =   32.50

----------------------

 

Multiply equation 1 by -.1 to eliminate the L term:

 

 -.1L  -  .1M  = -12.5

  .1L  + .5M  =  32.50

------------------------

.4M = 20

 

Divide both sides by .4:

 

M = 50

 

You could buy 50 mylar balloons.

 

Use equation 1 to solve for L:

 

L + 50 = 125

 

Subtract 50 from both sides:

 

L = 75

 

You could buy 75 latex balloons.

 

Check:

 

75 + 50 = 125

 

.1 * 75 + .5 * 50 = 32.50

 

7.5 + 25.0 = 32.50

 

32.50 = 32.50

 

Values check.

 

Questions?