Unit 4: More Working with Percent
Unit 4 Review: More Working with Percent
Review
You have been practising three types of percent problems. You have learned that one proportion can be used to solve all the problems:
- Finding a Percent of a Number
- You are given the percent and the whole.
- The missing term is the part (call it N). [latex]\dfrac{\textit{N}}{\text{whole}}=\dfrac{\%}{100}[/latex]
- Finding What Percent One Number is of Another
- You are told the part and the whole.
- The missing term is the percent (call it P). [latex]\dfrac{\text{part}}{\text{whole}}=\dfrac{\textit{P}}{100}[/latex]
- Finding a Number When a Percent of it is Given
- You are given the part and the percent.
- The missing term is the whole (call it W). [latex]\dfrac{\text{part}}{\textit{W}}=\dfrac{\%}{100}[/latex]
Real-life situations and real math problems often require several steps to collect and organize all the information. Look for those extra steps in the problems that follow. When you read the problems look for the part, the whole and the percent. Decide which term is missing. Once you know which term is missing the problem can be solved by using the proportion [latex]\dfrac{\text{part}}{\text{whole}}=\dfrac{\%}{100}[/latex] or the appropriate short method.
Questions
Solve these problems using proportion. Write all your work with the problem so your instructor can help you should you have any difficulty. Remember to check that the answer makes sense and to write a sentence answer. For these problems, round your answers this way:
- Percents to the nearest tenth of a percent
- Money to the nearest cent
- Decimal fractions to the nearest thousandth
- You need a minimum of 80% on the test which means you must get at least 36 marks. What are the total possible marks on the test?
- Ann and Joe bought their home twelve years ago and have paid 45% of the principle amount of their mortgage. They have paid $18,000 towards the principle of the mortgage. What was the principle amount of the mortgage to start with?
- The waiters at the restaurant must contribute money to be shared among the cocktail servers and kitchen staff. Each waiter contributes 4% of his or her total food and drink sales. Craig’s total sales were $645 in his 5 hour shift.
- How much money must he contribute to the kitchen and cocktail servers?
- Craig made 12% in tips on his sales tonight. What amount were his tips?
- The cost of hydroelectric power for our home last year was 210% of what it was six years ago. Last year our power bill totalled $960. How much was it six years ago?
- 16⅔% of the tickets for the rock concert were sold in the first hour the telephone order lines were open. In that hour, 2,500 tickets were sold. What was the total number of tickets available for the concert?
- The total student enrolment in the school district has increased from 18,506 students to 19,724 students in the last year. What is the percent of this increase in student enrolment?
- Al bought his secondhand off-ro