A survey of 10 random people in one town asked how many phone calls
they received in one day. The results were 1
,
5
,
3
,
2
,
4
,
0
,
3
,
6
,
8 and 2.
The mean was 3.4..
30
Taking 3 more surveys of 10 random people added more data. The means
of the new surveys were 1.2
,
2.8
, and 2.2. Based on the new data, Ann's
assumption that 3.4 calls
was average seems to be incorrect.
2. Raul surveyed 4 groups of 10 random people in a second town to ask
how many phone calls they receive. The
means of the 4 groups were
3.2, 1.4, 1.2, and 2.1. What can
you say about the number of phone
calls received in the towns
surveyed by Ann and Raul?