Nursing Preparation Study Guide

Nursing Preparation Study Guide

3.3 Percentages We are familiar with the word ‘percentage’ and often use it to describe interest rates, growth in sales, exam scores, etc. For example, if a student scored 85% on their TEAS examination, it would mean they got 85 questions correct out of 100: 85 100 % But what does percent or percentage mean? Percent is generally used to describe any value ‘out of 100’, which means ‘divide by 100’. The denominator, however, does not always default to 100. In that case, make the denominator 100 by multiplying the factor by a scaler. For example, suppose Randall scored 15 out of 20, then the fraction becomes: 15 20 Now, multiply both numerator and denominator by 5 so that the denominator becomes 100. 15 20 ∗ 5 5 = 75 100 = 75% Let us consider another case, where you have scored 65 out of 75. Now in this case, multiply and divide the fraction by 100 and substitute the 100 in denominator as % sign and simplify the same: 65 75 ∗ 100 100 = 65 75 ∗ 100 % = 86.67% Sometimes we need to find the percentage of a particular value--for example, calculating a 10% tip on a restaurant check of $460. To do this, find 10 percent of $460. Mathematically, 10 100 ∗ 460 = $46 3.3.1 Converting Fractions to Percentages A fraction is nothing more than a division problem: you’re dividing the bottom number into the top number. So for instance, if we start with a fraction <

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