The number of boys and girls in a school are in the ratio 5: 7. What is the number of girls if 1200 boys are there in the school.

25 ! the line of best fit is h = 5a + 86. predict the height at age 16.

Jenisey has $24 to spend on seven pencils. after buying them she had $10. how much did each pencil cost.?

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.