Math Practice Test Set 2

1. \(\frac{8}{y+6}\)

Find the value that makes this rational expression undefined.

2. Mia goes to East York Collegiate Institute. She is given the following information:

There are 150 grade 12 students at East York Collegiate Institute. 70 of the grade 12 students drive a car at the school. Half of all students with a grade average of 90 or higher have a car.

She is asked to find the probability of randomly choosing a grade 12 student with a car, given that the
student has an average grade of 90 or higher. She reasons initially that, since there are 70 grade 12 students out of 150 who have a car, it would be \(frac{7}{15}\). However, since it is a conditional probability, she needs to multiply by \(\frac{1}{2}\), since the probability that a student with a grade average of 90 or higher is \(frac{1}{2}\). This results in a probability of \(frac{7}{30}\). Is she correct or not, and why?

3. \(3x^{2} - 2y^{2}\) at \(x = −3\) and \(y = −2\)

4. Simplify the given expression.

−| − 40|

5. Evaluate the expression at the given value of x.

\(4x^{2} + 2x + 6\) at \(x = −6 \)

6. Convert the given percent to a decimal.

8%

7. Use the elimination method to solve each of the following systems.

x + 9y = 73
−4x − 5y = −44

8. Use the elimination method to solve each of the following systems.

−12x + 9y = 0
−6x − 4y = −34

9. Use the elimination method to solve each of the following systems.

3x − 7y = −75
−2x − 2y = −10

10. A student’s bank account is overdrawn. After making a deposit of $360, he finds that his account is still overdrawn by an amount of $90. What was his balance before he made his deposit?