# Math Help - Through what angle does the arrow rotate when it moves 1 inch on the gauge?

1. ## Through what angle does the arrow rotate when it moves 1 inch on the gauge?

The arrow on a car’s gasoline gauge is ½ inch long. Through what angle does the arrow rotate when it moves 1 inch on the gauge? Give your answer in degrees (round to the nearest whole degree).

I got 115 degrees as an answer and i wanted to see if i got it right.

2. ## Re: Through what angle does the arrow rotate when it moves 1 inch on the gauge?

A full circle, 360 degrees, with radius 1/2 in. has circumference $2(\pi)(1/2)= \pi$ in. The angle, A, making an arc of 1/2 inch is given by the proportion: $\frac{A}{360}= \frac{1}{\pi}$.