Question

For 10 days in a row Fiona and Gary timed how long they brushed their teeth

Answer 1

(X (Fiona) + Y (Gary))/20 (10 days for each of them so it’s 20)

(x+y)/6

Answer 2

The mean or the average of a number is calculated by adding the frequencies of the given data and then dividing by the total frequency. It is represented by the formula mentioned under -

Mean = $\frac{Sum of all the frequencies}{Number of frequencies}$

Similarly, here, we need to find the mean of their time spent in brushing.

It will be calculated as -

For Fiona

Mean of time spent in brushing = $\frac{Sum of the total time spent in 10 days}{10 days}$

Similarly, for Gary

Mean of time spent in brushing = $\frac{Sum of the total time spent in 10 days}{10 days}$