What is the standard deviation of the data set? round your answer to the nearest tenth.
6 4 9 5 5 4 5
a. 1.7
b. 1.6
c. 5.0
d. 5.4

Assume that the weights of quarters are normally distributed with a mean of 5.67 g and a standard deviation 0.070 g. a vending machine will only accept coins weighing between 5.48 g and 5.82 g. what percentage of legal quarters will be rejected? round your answer to two decimal places.

The diagram shows corresponding lengths in two similar figures. find the area of the smaller figure. a. 14.4 yd2 b. 24 yd2 c. 26.4 yd2 d. 28

Select all of the following expressions that are equal to 2.5.