Exam 31: Proportions

Solve the proportion for the unknown term ( x ): 64:8 = x :16 .

Solve the proportion for the unknown term ( x ): 3.5:1= x :14 .

The diameter of a driving pulley is 12.75 inches. The pulley is rotating at 225 rpm. The driving pulley is rotating at 450 rpm. Determine the diameter in inches of the driver pulley.

On method for solving proportions is to set up the two ratios as equal fractions and then cross multiplying.

Solve the proportion for the unknown term ( x ): 350/7 = 150/ x.

In a proportion, the extremes are the two inside terms.

Solve the proportion for the unknown term ( x ): 18.9/5.4 = 21/ x .

A CAD operator realizes that it takes 36 minutes to plot a drawing. How long in hours will it take to plot 30 hard copies of the same drawing?

A gear with 24 teeth and running at 120 rpm is being driven by a gear turning at 360 rpm. How many teeth does the driving gear have?

In two weeks, 3 machinists assemble 30 machines. How many machinists are needed to assemble 100 machines in the same times?