Proportions Application

Question

Junko makes cookies at the rate of two dozen per one hour and fifteen minutes.  She has to make a total of 216 cookies for a wedding party.  How long will it take her?

Answer 1

24 cookies per 1 hour and 14 min ---> 24 cookies per 1 + 1/4 hours --> 24 cookies per 5/4 hours

24 in proportion to 5/4 hours

equals

216 in proportion to ????

24 * ? = 5/4 * 216

? = 5/4 * 216 / 24

= 5/4 * 216/24

= (5*216)/(4*24)

= (5*216)/96

= 5*108/48

= 5*54/24

= 5*27/12

= 5*9/4

= 45/4

= 11 + 1/4