#### kaylor koh

##### New member

- Joined
- Sep 20, 2009

- Messages
- 12

1.Find the area under the standard normal curve between z = 1.5 and z = 2.5

The answer I got is 0.927, but it seems wrong.

I used -1.5 and 2.5

So I got 0.9938-0.0668=0.927

2.(I have absolutly no idea for this quest)

The local lottery sets up a game wherein a player has a chance of collecting $750.

The player must choose a 3-digit number and if it matches, the player receives $750

Remember, 000 is a 3-digit number for lottery draws.

It costs $1 to play the game.

What is each player's expected profit (or loss).

3.0.5 of all college students like the idea of a new curriculum.

If we select 93students (ASSUME INDEPENDENCE), what is the Standard Deviation of the Probability Distribution that would list the number of students (from 0 to 93) and the probability of each

4.A tire company finds the lifespan for one brand of its tires is normally distributed with a mean of 49,300 miles and a standard deviation of 6000 miles. If the manufacturer is willing to replace around 10% of the tires as unsatisfactory performers, what should be the approximate number of miles for a warranty?

5.The probability Mary will receive an A in a class is 0.49.

Assuming independence, if she is taking 5 classes this semester, calculate the probability she will receive exactly 3 A's.

The answer I got is 0.3060 using the bio formula

6.test scores are Normally Distributed with a mean of 73 and a Standard Deviation of 10.

Calculate the z-score of a test score of 49

Answer: 0.0082

7.A mail-order company receives an average of five orders per 500 solicitations. If it sends out 100 advertisements, find the probability of receiving at least two orders

Answer:0.1839 using poisson rule