Question

1) If N is the set of natural numbers that are factors of 18, represent this set in roster form.

2) Suppose U={1,2,3,4,5,6,7,8,9,10} is the universal set and A={1,4,5,9,10} What is A?

3) The wrestling team is holding a car wash. The teams goal is to raise at lease 252 and each car wash cost 5.25.
a) Write an inequality to represent this situation.

4) A student scored a 78 and 93 on his first two assignments respectively. He wants an average between 88 and 90.
a) Write a compound inequality representing the possible values for the a third assignment so his average is between 88 and 90.

6) John is at a car show. Beginning 2.5 miles away, a car traveling at a constant 45 miles per hour approaches and then passes John. The distance between John and the car can be represented by the equation d=/2.5-4.5t/. at what times is the car 0.5 miles from john?

Answer 1

1. 18 = 1*18 = 1*2*9 = 1*2*3*3.
Factors: N = {1,2,3,9,18}.

3a. 5.25x => 252

4a. Inequality: 88 < (78+93+x)/3 < 90

264 < 171 + x < 270
93 < X < 99

The inequality says: (78+93+x)/3 is
greater than 88 but less than 90.