Question

what is the ratio of the sector area to the area of the entire circle?
1/5
1/2
2
4

Explanation:

Step1: Recall the formula for the ratio of sector area to circle area

The ratio is $\frac{\theta}{360^{\circ}}$, where $\theta$ is the central angle of the sector.

Step2: Substitute the given central angle

Given $\theta = 72^{\circ}$, so the ratio is $\frac{72^{\circ}}{360^{\circ}}=\frac{72}{360}=\frac{1}{5}$.

Answer:

$\frac{1}{5}$ (First option)