Statistics And Sets Problems, Word Problems

[swerve]

A preschool classroom 20 three-years-old and 10 four-years-old. The average height for the three-years-old is 37 inches, and the average height for the four-years-old is 40 inches. What is the average height of the 30 students in the classroom?

A. 37 inches
B. 37.5 inches
C. 38 inches
D. 38.5 inches
E. 39 inches

The OA is C

Source: Veritas Prep

[Scott@TargetTestPrep]

A preschool classroom 20 three-years-old and 10 four-years-old. The average height for the three-years-old is 37 inches, and the average height for the four-years-old is 40 inches. What is the average height of the 30 students in the classroom?

A. 37 inches
B. 37.5 inches
C. 38 inches
D. 38.5 inches
E. 39 inches

The OA is C

Solution:

The average height of the 30 students in the classroom is:

(20 x 37 + 10 x 40) / 30 = (740 + 400)/30 = 1140/30 = 38 inches

Answer: C