# PERT Math Practice Quiz 3

#### The angle for B is 198 degrees. How many shoppers purchased B?

The number of degrees in a circle is 360. The total number of people purchasing cleaner was 300. The angle for those who bought B was 198. The number who bought B was 198/360 x 300 = 165.

#### What percentage of students who got a mark below 30 got a mark below 20?

The number of students who got a mark less than 30 was 23 + 32 + 45 = 100. The number of students who got a mark less than 20 was 23 + 32 = 55. The percentage of students who got a mark less than 30 who got a mark less than 20 was 55÷100 = 55%.

#### Which of these is true?

The symbol for square root is √. The square roots of negative numbers are undefined.

#### Given the formula a = s2 + 3b - c , find the value of a when s = 7, b = 13 and c = -24.

Substitute for s, b and c. a = 72 + 3(13) - (-24) a = 49 + 39 + 24 = 112.

#### What is the value of (x2 + x + 3) / (x + 2) when x = -1?

Although T is negative for 1 < t = 0 for t >= 3 T > 0 for t < -1. T < 0 or negative when -1< t < 3

#### There is a 12% sales tax. The pre-tax cost of a mobile phone is $280. What is the tax payable on this mobile phone?

The sale price of the phone is 1.12×280 = $313.60. The tax is $313.60 - $280 = $33.60.

#### The graph below is part of the graph of the function T = (t + 1)(t - 3) for the temperature in a refrigerator for time t hours after midday. For which set of t values is the temperature below 0?

Adding 10 to n gives n + 10. Multiplying the number obtained by 3 gives 3(n + 10). Making this equal to 42 gives 3(n + 10) = 42.

#### What number should replace x?

For 26 hours they are paid 26×$25 = $650. The money they get for overtime is $850 - $650 = $200. The number of overtime hours is $200÷$40 = 5. x is 5.

#### There are 1,000,000 kb in a GB. Guy has 29 GB of storage on his computer. He has a lot of picture files of about 78kb. What is the maximum number of such pictures he can store on his computer?

There are 1,000,000 kb in a GB. In 29GB there are 29,000,000kb. Guy can store 29,000,000÷78 = 371,794.87.... pictures. He can store 371,794 complete pictures