A **ratio **is a comparison of 2 quantities. The focus of this article is writing a ratio.

### Ratios in Daily Life

- 60 miles per 1 hour
- Cost per text message
- 1 to 28,000,000 chance of winning the lottery
- 3 teachers per 76 students

### How to Write a Ratio

Dr. Pasture, a rural veterinarian, treats only 2 types of animals – cows and horses. Last week, she treated 12 cows and 16 horses.

Part to Part Ratio: What is the ratio of cows to horses that she treated?

Simplify: 12:16 = 3:4

Ratio Formats

- 3:4
- 3 to 4
- 3/4

For every 3 cows that Dr. Pasture treated, she treated 4 horses.

Part to Whole Ratio: What is the ratio of cows that she treated to the total number of animals that she treated?

Simplify: 12:30 = 2:5

Ratio Formats

- 2:5
- 2 to 5
- 2/5

For every 5 animals that Dr. Pasture treated, 2 of them were cows.

### Exercises

Use the demographic information about the marching band to complete the following exercises.

Dale Union High School Marching Band

Gender

- 120 boys
- 180 girls

Instrument type

- 160 woodwinds
- 84 percussionists
- 56 brass players

Class

- 127 Freshmen
- 63 Sophomores
- 55 Juniors
- 55 Seniors

1. What is the ratio of boys to girls?

2. What is the ratio of freshmen to the total number of band members?

3. What is the ratio of percussionists to the total number of band members?

4. What is the ratio of juniors to seniors?

5. What is the ratio of sophomores to juniors?

6. What is the ratio of freshmen to seniors?

7. If 25 students left the woodwind section to join the percussion section, what would be the new ratio of woodwinds to percussionists?