The batting averages of the first three batters in the Eureka College women’s softball team lineup are .310, .301, and .277. If the first three batters are considered as the “lead-off group”, what is the batting average of the group?

mean = ∑x/n = (.310 + .301 + .277)/3 = ?

1. On the basis of past experience, the buyer for a large sports store estimates that the number of 10-speed bicycles sole next year will be somewhere between 40 and 90 – with the following distribution:

Number of Bicycles Sold x Probability P(x)
40 0.05
50 0.15
60 0.41
70 0.34
80 0.04
90 0.01
a. What is the mean number sold? What is the standard deviation?
b. If 60 are ordered, what is the chance they will all be sold? What is the chance some will be left over?
c. To be almost sure (say, 95% sure) of having enough bicycles, how many should be ordered?

To calculate the batting average of a group, you need to add up the individual batting averages and divide the total by the number of batters in the group. In this case, the lead-off group consists of three batters.

The batting averages of the first three batters are:
- First batter: .310
- Second batter: .301
- Third batter: .277

To find the group's batting average, you add up the three individual batting averages and divide the total by 3 (the number of batters in the group):

(.310 + .301 + .277) / 3

Calculating this expression will give you the answer, which is the batting average of the lead-off group.