Question

19

Standard 7.4(D) -- Readiness
1
A bicycle shop designs a new gear system for
their bikes. They use a 4-inch gear for bikes
with a 22-inch wheel diameter. If the ratio of
the gear to wheel diameter remains constant,
what is the size of the gear for a bike with a
26-inch wheel?

Answer 1

4.72

Explanation:

In order to solve this problem you need to setup a proportion. A proportion is two equivalent ratios. The problem gives you the first ratio, 4 inch gear to 22 inch diameter.

`(4)/(22)  = (g)/(26)`

Then you will cross multiply and end up with 22g = 104

For the final step, you will divide both sides by 22, in order to isolate the variable g.

g = 4.72

or in other words, the size of the gear for a bike with a 26 inch wheel, is 4.72 in.