Question

The table below shows the weight of 21 students (on the left) and the corresponding number of students with that weight (on the right). Compute the Mean of the data below.

Weight No. of Students

34 5

39 8

43 2

45 6

Answer 1

Represent the weight by $x$ and the number of students by $f$.

Now,

$x$ $f$ $fx$

34 5 170

39 8 312

43 2 86

45 6 270

The mean, $\bar x={\sum fx\over \sum f}={838\over21}=39.90(2dp)$