Question

the following table shows the data collected from students in grades 3 and 4 in an elementary school about their favorite types of pets.

	cats	dogs	birds	other	total
grade 4	35	50	15	10	110
total	60	110	20	25	215

which of the following statements is supported by the table?
a dogs were the type of pet chosen most often by the students at the elementary school.
b there were more students surveyed in grade 3 than in grade 4.
c the percentage of students who chose cats as their favorite pet was 60%.
d the percentage of students in grade 3 who chose dogs as their favorite pet was 55%.
e birds were the type of pet chosen least often by the students in grade 4.

Explanation:

Step1: Analyze option A

Total number of students who chose dogs is 110, which is more than the total number of students who chose cats (60), birds (20) and other (25). So dogs were chosen most often.

Step2: Analyze option B

Number of students surveyed in grade 3 is 105 and in grade 4 is 110. So more students were surveyed in grade 4, not grade 3.

Step3: Analyze option C

Percentage of students who chose cats is $\frac{60}{215}\times100\%\approx 27.9\%
eq 60\%$.

Step4: Analyze option D

Percentage of grade - 3 students who chose dogs is $\frac{60}{105}\times100\%\approx 57.1\%
eq 55\%$.

Step5: Analyze option E

In grade 4, the number of students who chose other (10) is less than the number of students who chose birds (15). So birds were not chosen least often in grade 4.

Answer:

A. Dogs were the type of pet chosen most often by the students at the elementary school.