Question

The table below shows school T-shirt sales for the past ten weeks. The school wants to make one more order for the next 30 weeks. How could the school decide how many T-shirts to order?

Date:
Sept Sept Sep Oct Oct Oct Oct Oct Nov Nov
10 17 24 1 8 15 22 29 5 12
Sales:
7 50 8 9 10 12 7 7 9 11
1. What are the mean, median, mode, and range of the T-shirt data shown above?
2. Compare the mean, median, and mode. Which measure seems to best represent the ten numbers? Explain

Answer 1

Mean =13, Median=9, Mode =7, Range=43

Explanation:

(1)Mean

`Mean =\frac{\text{Sum of all the Sales}}{\text{Number of Sales}}`

`=(7+50+8+9+10+12+7+7+9+11)/(10)\\=(130)/(10) \\\bar x =13\\Mean=13`

Median

First we arrange the sales in ascending order

7,7,7,8,9,9,10,11,12,50

Since there are two terms in the middle, the Median =(9+9)/2 =9

Mode

The mode is the number of sales with the highest frequency.

Mode =7

Range

Range =Highest Value - Lowest value =50-7=43

(b)Mean =13, Median=9, Mode =7, Range=43

The Median seems to best represent the ten numbers. this is as a result of the fact that the value of the Mean and range were affected by the outlier number(50).

The School should therefore order T-Shirts in the range of the Median.