Example Problems Answers

Solve the proportions:

1.                  2.           3.

    9(x+2) = 6(12)                  24x = 12(144)        10(x-6) = 12x     
    9x+18=72                         24x = 2160               10x-60=12x
     9x = 54                               x = 90                       -60 = 2x
       x = 6                                                                  -30 = x
 

Use proportions to solve:

4. If Jamie drives 264 miles in 4 hours, how many miles can she
    drive in 20 hours?
            264  =  x             4x = 5280
             4       20              x = 1320 miles

5. If 1.3 cm on a blueprint represent 20 miles, how wide is a lake
     measuring 6.4cm?

            1.3  =  6.4            1.3x = 128
           20        x                x = 98.46 miles wide

                    4x - 6 = 1/2(100)
             4x - 6 = 50
              4x = 56       x = 14