Question

The figure below shows a shaded rectangular region inside a large rectangle: (pic)

What is the probability that a point chosen inside the large rectangle is not in the shaded region?
A) 8%
B) 16%
C) 50%
D) 84%

Answer 1

D

Explanation:

Probability of falling NOT in the shaded region is "area of white region" divided by "area of whole rectangle (big one)".

Area of whole rectangle:

Area of rectangle = length * width = 10 * 5 = 50

Area of White Region:

First, area of shaded region = length * width = 4 * 2 = 8

Now,

Area of white region = area of whole rectangle - area of shaded rectangle

Area of white region = 50 - 8 = 42

Hence, probability is
`(42)/(50)=0.84`

0.84 = 84%

Answer choice D is right.