Problem Solving With Percents
We could have used equivalent fractions instead (i.e., since 20 multiplied by 5 equals 100, we get that 8 multiplied by 5 equals x, so x equals 40).In Problem 1 we were asked 8 is what percent of 20?
Plus, get practice tests, quizzes, and personalized coaching to help you succeed.Analysis: In this problem, you are being asked 8 is what percent of 20?You are given two numbers from the proportion above and asked to find the third.." If any two of the variables are given, you can use algebra to find out the missing one. In each one, the unknown is in a different position.In previous lessons, you were shown how to convert a decimal to a percent and a percent to a decimal.20% means that 20 will replace percent in our proportion. Substitute: Now we can substitute these values into our proportion.becomes Solve: Cross multiply and we get: 100x = 45(20) or 100x = 900 Divide both sides by 100 to solve for x and we get: x = 9 Solution: 9 is 20% of 45 In Problems 1, 2 and 3 we are given two numbers and asked to find the third by using a proportion.14 is the part and will replace IS in our proportion.PERCENT is the unknown quantity in our proportion, to be represented by n.This is not surprising since our original statement is, "One number is some percent of another number." Thus, we can revise our proportion as follows: becomes Let's solve some more percent problems using proportions. Identify: 25% means that 25 will replace PERCENT in our proportion.52 is the whole and will replace OF in our proportion.