You want to investigate the average amount of time people aged 20 to 40 spend on the phone each week. Interpret the chart below by finding the group mean of the hours spent on the phone. Age Hours 20-22 45 23-25 36 26-28 25 29-31 16 32-34 12 35-37 8.5 38-40 4 Histogram

 Problem

You want to investigate the average amount of time people aged 20 to 40 spend on the phone each week. Interpret the chart below by finding the group mean of the hours spent on the phone.

Age	Hours
20-22	45
23-25	36
26-28	25
29-31	16
32-34	12
35-37	8.5
38-40	4

 

Solution 

In this problem, in order to interpret the chart you where asked to,

• Interpret the chart by finding the group mean of the hours spent on the phone

To find the group mean, you simply have to follow the formula,

  

Age	Hours
20-22	45	21	945
23-25	36	24	864
26-28	25	27	675
29-31	16	30	480
32-34	12	33	396
35-37	8.5	36	306
38-40	4	39	156
Total	146.5		3822

 

Plugging this into the formula, you get,

  

Which means that the group average is ages 26-28. This can be seen in the chart below.