Tackling Basic Percentage Problems

The nice thing about percents is that their values are easy to relate to. If you re 75 percent finished with a project, then you know that you re well on your way. You compare the percentage to 100 — a nice, round number — and have a good idea of what the value is in the comparison. To be more exact with an answer, though, you need to convert percentages to decimals and create a more exact value to use in computations. Using the decimal equivalents, you can solve for the percent of a value and get the answer in items, and you can also solve for how many items are needed to reach a certain percent. 

When you re told that you have 60 percent of the work done or 85 percent of the problems correct, you multiply the total number of hours needed to do the work or the total number of problems on the test by the percent to get the numerical value of what you re discussing. Percents are convenient amounts for comparison. You convert percents to decimals to use them in problems. 

The Problem You sign up for Weight Watchers, and you re told that you need to lose 10 percent of your current weight. If you weigh 160 pounds, how much do you need to lose  

Changing 10 percent to a decimal, you get 0.10. Multiply 160 x 0.10 and you get 16 pounds. That should be a piece of cake. Oops Not on Weight Watchers — make that a carrot stick. 

The Problem You re told that 95 out of 100 of the people who buy a Honda motorcycle will buy another Honda when they need to buy another motorcycle. Last year, the number of Honda motorcycles sold in North America was 570,000. How many of these owners will buy a Honda when they make their next motorcycle purchase  

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