Math

Week 6 – Real world applications problems

1. The length of fencing available to secure a garden plot is only 280 feet. We need to find out what is the maximum area of a square plot that can be fenced using the entire 280 feet of fencing. Use your knowledge of graphing to solve this problem.

2. You have moved into a new apartment and want to select a plan for a land phone line. Phone Company A offers $10 as a line charge and 10 cents per minute for calling time. Phone Company B offers $15 as a line charge and 7 cents per minute for calling time. Your average calling time is 500 minutes per month. Which plan would be beneficial to you. Use your knowledge of graphing to show how you made your decision.

3. You invested $10,000 on a machine that can be installed I your garage to produce some plastic items which can sold in bulk at $1.25 per unit. It costs $0.65 per unit to produce inclusive of labor, materials and energy. How many units would you have to produce to breakeven? Show graphically in which region you will make a profit and in which region you will make a loss.

4. A person’s intelligence quotient (I) is found by dividing mental age (M), as indicated by standard tests, by chronological age (C) and then multiplying this ratio by 100. The formula I = (100M)/C can be used. If I range of a group of 11-year-olds is given by 80 ≤ I ≤ 140, find the range of the mental age of this group.