Question

use the information about the animals in a pet st

• 38% of the animals are dogs.
• 40% of the animals are spotted.
• 12% of the animals are spotted dogs.

what percent of the animals in the store are spotted or
a. 54%
b. 66%
c. 78%
d. 80%

Explanation:

Step1: Apply addition rule for sets

Let $P(D)$ = % of dogs, $P(S)$ = % of spotted animals, $P(D \cap S)$ = % of spotted dogs. The formula for $P(D \cup S)$ is $P(D) + P(S) - P(D \cap S)$.

Step2: Substitute given values

$P(D)=38\%$, $P(S)=40\%$, $P(D \cap S)=12\%$.
Expression: $38\% + 40\% - 12\%$

Step3: Calculate the result

$38 + 40 - 12 = 66$

Answer:

B. 66%