Answer:
15.71 ft
Step-by-step explanation:
Given that:
width of the circular track = 2.5ft
Suppose the radius of the inner circle is 57 ft since it is not given
Then the radius of the outer circle = (2.5 + 57) ft = 59.5 ft
The circumference of a circle = 2πr
For inner circle now, the circumference = 2 × π × 57 ft
For inner circle now, the circumference = 358.14 ft
For the outer circle, the circumference = 2 × π × 59.5 ft
For the outer circle, the circumference = 373.85 ft
The difference between the circumference of the outer wheel from the inner wheel shows how farther does a wheel on the outer rail travel than a wheel on the inner rail of the track in one turn
∴
= ( 373.85 - 358.14 ) ft
= 15.71 ft
Hello! Your answer is B, 10 minutes.
Say the x = minutes taken to do the job. You can set up an equation like this to solve this.

This is representative of the situation. The fractions each represent <u>how much each person does in a minute</u>, and when they're multiplied by x, that's <u>how much of the project they get done</u> based off of the minutes they work together on the job. Add the two together, and you get <u>how much of the project is finished in x amount of time</u>. Set it equal to 1, as you are looking for 100% completion.
Once you have this equation, find a common denominator, add, and solve.





Therefore, it will take them 10 minutes to do the job together.
Hope this helps!