5.5 Percent Proportion: Find the Part

5.5 Percent Proportion

TEKS 6.5B

I can solve problems involving percents.

​Percent Proportion

​You can use a proportion to solve problems involving percents.

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​One ratio is the percent. Remember that percent is always out of 100.

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​The other ratio is the part to whole comparison.

Example

​75% of the 6th grade class is making a B or higher. If there are 24 students in the 6th grade class, then how many are making a B or higher?

• ​In this example, we know that the percent is 75%, or 75 out of 100.

• ​We also know that there are a total of 24 students, so 24 is the whole amount.

• ​We are asked how many are making a B or higher, so we are looking for what part of the class is making a B or higher.

Multiple Choice

A campus survey states that 40% of students ride the bus. If there are 300 students, how many ride the bus?

Which proportion could be used to solve this problem?

• $$\frac{x}{100}=\frac{40}{300}$$  

• $$\frac{40}{100}=\frac{300}{x}$$  

• $$\frac{100}{300}=\frac{x}{40}$$  

• $$\frac{40}{100}=\frac{x}{300}$$  

​Answer

A campus survey states that 40% of students ride the bus. If there are 300 students, how many ride the bus?

• ​The percent is 40%, or 40 out of 100

• ​There are a total of 300 students.

• ​Need to find what part of the students ride the bus.

Remember

To solve a proportion:

1. ​Cross multiply - bottom of one ratio times top of the other ratio.

2. ​Divide by the number next to the x in the resulting equation.

Multiple Choice

A local zoo had 750 visitors on Saturday. If 80% of the guests lived in the same town as the zoo, how many local guests visited the zoo on Saturday?

Choose the correct proportion to solve this problem.

• $$\frac{80}{100}=\frac{x}{750}$$  

• $$\frac{80}{750}=\frac{x}{100}$$  

Multiple Choice

A local zoo had 750 visitors on Saturday. If 80% of the guests lived in the same town as the zoo, how many local guests visited the zoo on Saturday?

• 620 local guests

• 600 local guests

• 9 local guests

• 650 local guests

Multiple Choice

On an average Sunday, 460 tickets are sold. How many children's tickets were sold?

Which proportion could be used to solve this problem?

• $$\frac{15}{460}=\frac{x}{100}$$  

• $$\frac{15}{100}=\frac{x}{460}$$  

Multiple Choice

On an average Sunday, 460 tickets are sold. How many children's tickets were sold?

• 69 tickets

• 63 tickets

• 74 tickets

• 70 tickets

Multiple Choice

The zoo has 40 dispensers to buy food to feed the animals. Thirty percent of the dispensers are for land animals. How many of the dispensers are for land animals?

• 13 dispensers

• 15 dispensers

• 10 dispensers

• 12 dispensers

Multiple Choice

Of the 250 visitors on Friday, 54% of them stayed until the zoo closed. About how many visitors stayed until the zoo closed?

• 130 visitors

• 125 visitors

• 135 visitors

• 140 visitors

Multiple Choice

A guest survey showed that 325 people ordered food while at the zoo. Ninety-two percent were satisfied with their food order. How many people were not satisfied with their order?

• 28 people

• 26 people

• 29 people

• 32 people

Multiple Choice

There are 20 different places to get food. Twenty percent of them are ice cream shops. How many ice cream shops are in the zoo?

• 10 ice cream shops

• 3 ice cream shops

• 5 ice cream shops

• 4 ice cream shops

Multiple Choice

The zoo has 400 employees. 28% of them are full-time employees. How many employees work full-time?

• 112 full-time employees

• 100 full-time employees

• 115 full-time employees

• 118 full-time employees

Multiple Choice

Of the 400 employees, 5% of them are managers. How many managers does the zoo employ?

• 30 managers

• 20 managers

• 25 managers

• 35 managers