In order to find the probability, first we need to calculate the triangle area and the circle area.
The triangle has a base of 8 cm and a height of 4 cm, so its area is:
![A_t=(8\cdot4)/(2)=4\cdot4=16\text{ cm}^2](https://img.qammunity.org/2023/formulas/mathematics/college/ijoz4besv45w1sqvq81gif4ser9r03umey.png)
The circle has a radius of 4 cm, so:
![A_c=\pi r^2=3.1416\cdot4^2=50.2656](https://img.qammunity.org/2023/formulas/mathematics/college/n8bdcd05vzpowzcl0hvqseob2be4iavbib.png)
Now, to find the probability, we divide the white area (circle minus triangle) by the total area (circle):
![P=(A_c-A_t)/(A_c)=(50.2656-16)/(50.2656)=(34.2656)/(50.2656)=0.68169](https://img.qammunity.org/2023/formulas/mathematics/college/sqpr9t3a6uompgpi23eo113ag66tw65yqj.png)
Rounding to the nearest tenth of a percent, we have a probability of 68.2%.