Answer:
The circumference of the back wheel is 2.62 inches
Step-by-step explanation:
Given
[tex]d_1 = 5in[/tex] --- diameter of front wheel
[tex]d_1 : d_2 = 3:1[/tex] --- ratio of the diameters
Required
The circumference of the back wheel
First, we calculate the diameter of the back wheel.
We have:
[tex]d_1 : d_2 = 3:1[/tex]
Substitute: [tex]d_1 = 5in[/tex]
[tex]5in: d_2 = 3 : 1[/tex]
Express as fraction
[tex]\frac{d_2}{5in} = \frac{1}{3}[/tex]
Make [tex]d_2[/tex] the subject
[tex]d_2 =5in * \frac{1}{3}[/tex]
[tex]d_2 = \frac{5}{3}\ in[/tex]
So, the circumference (C) of the back wheel is:
[tex]C =\pi d[/tex]
[tex]C = 3.14 * \frac{5}{6}\ in[/tex]
[tex]C = \frac{3.14 * 5}{6}\ in[/tex]
[tex]C = \frac{15.7}{6}\ in[/tex]
[tex]C = 2.62\ in[/tex]