Homework Answers

An aptitude test for selecting officers in a bank was conducted on 1,000 candidates, the average score is 42 and the standard deviation of scores is 24. Assume that the scores are normally distributed, answer the following questions.

What is the probability that the candidates score,

Exceed 65?

Between 40 and 60?

Find the number of candidates whose score,

Exceed 40?

Lie between 40 and 65?

average score is 42 and the standard deviation of scores is 24. Assume that the scores are

normally distributed answer the following questions

What is the probability that the candidates score

A. Exceed 65

B Between 40 and 60

Find the number of candidates whose score

A Exceed 407

The region bounded by the graphs of y= √x and y= x²

The region bounded by the graphs of y= x² and y= x+2

A cylindrical tank of radius 5 ft and height 9 ft is two-thirds filled with water. Find the work required to pump all the water over the upper rim.

(Assuming the tank is half-filled with water)

Assume that 10 ft-lb of work is required to stretch a spring 1 ft beyond its natural length. What is the spring constant?

A spring exerts a force of 100 N when it is stretched 0.2 m beyond its natural length. How much work is required to stretch the spring 0.8 m. beyond its natural length?

A flat rectangular plate is submerged horizontally in water

a. Find the force (in lb) and the pressure (in lb/ft²) on the top surface of the plate if its area is 100 ft² and the surface is at a depth of 5 ft.

b. Find the force (in N) and the pressure (in Pa) on the top surface of the plate if its area is 25 m² and the surface is at a depth of 10 m.

A sample of students from an introductory psychology class were polled regarding the number of hours they spent studying for the last exam. The data was used to make inferences regarding the other students taking the course. There data are below:

8 22.7 14.5 9 9 3.5 8 11 7.5 18

20 7.5 9 10.5 15 19 9 8.5 14 20

Compute a 99% confidence interval.