According to the national sleep foundation, teenagers need about 9 hours of sleep each night to function at their best. unfortunately, many teens do not get nearly this amount. two samples of 100 teenagers were asked about the average number of hours they sleep each school night. the results are recorded in the table below.

< 4
4 - 6
6 - 8
8 - 10
10 +
sample #1
2
9
39
44
6
sample #2
1
12
34
48
5
based on the results in the table, in a high school that contains 925 students, approximately how many of the students would you expect to get between 8 and 10 hours of sleep each school night?
425
850
340
445

Abcd is a parallelogram. the diagram is not drawn to scale. if m

Carley bought a jacket that was discounted 10% off the original price. the expression below represents the discounted price in dollars, based on x, the original price of the jacket.

An automobile assembly line operation has a scheduled mean completion time, μ, of 12 minutes. the standard deviation of completion times is 1.6 minutes. it is claimed that, under new management, the mean completion time has decreased. to test this claim, a random sample of 33 completion times under new management was taken. the sample had a mean of 11.2 minutes. assume that the population is normally distributed. can we support, at the 0.05 level of significance, the claim that the mean completion time has decreased under new management? assume that the standard deviation of completion times has not changed.