### Home > CCG > Chapter 7 > Lesson 7.2.4 > Problem7-88

7-88.

Kendrick is frantic. He remembers that several years ago he buried his Amazing Electron Ring in his little sister’s sandbox, but he cannot remember where. A few minutes ago he heard that someone is willing to pay $\1000$ for it. He has his shovel and is ready to dig. Homework Help ✎

1. The sandbox is rectangular, measuring 4 feet by 5 feet, as shown below. If Kendrick only has time to search in the 2 foot-square shaded region, what is the probability that he will find the ring?

$2·2$ is what fraction of $5·4$?

1. What is the probability that he will not find the ring? Explain how you found your answer.

$\text{P(Kendrick finds the ring)}+\text{P(Kendrick doesn′t find the ring)}=1$

$\frac{16}{20}=\frac{4}{5}$

1. Kendrick decides instead to dig in the square region shaded below. Does this improve his chances for finding the ring? Why or why not?

Write a probability for this diagram and compare it to your fraction from part (a).