Question

The table shows the heights of 40 students in a class.

a) Calculate an estimate for the mean height of the students
b) Explain why your answer to part (a) is an estimate

Answer 1

A. 129.3

B. The students ages can be any number within the ranges, so having the middle number wont represent the other possible heights.

Step by step

'h' is the number between the surrounding number, the first would be 122.

You need to multiply the hight by frequency of each one,

122x7 =854

126x8=1008

130x13=1690

134x9=1206

138x3=414

Add them up = 5172

5172/40 =129.3