# What is ratio? #### Everything You Need in One Place

Homework problems? Exam preparation? Trying to grasp a concept or just brushing up the basics? Our extensive help & practice library have got you covered. #### Learn and Practice With Ease

Our proven video lessons ease you through problems quickly, and you get tonnes of friendly practice on questions that trip students up on tests and finals. #### Instant and Unlimited Help

Our personalized learning platform enables you to instantly find the exact walkthrough to your specific type of question. Activate unlimited help now!

##### Intros
###### Lessons
1. Introduction to What Is Ratio
##### Examples
###### Lessons
1. Understanding Ratio Tables

Fill in the blanks in the following ratio table.

 x y 4 8 14 21
1. Part-to-part Ratio Vs. Part-to-whole Ratio

There are 14 boys and 16 girls in a particular class.

1. Find the ratio of boys to girls.
2. Find the ratio of boys to the whole class.
2. Charlie bought 2 Superman action figures and they are 4.4 cm and 9 cm tall respectively. What is the ratio of the height of the smaller figure to the larger figure?
1. Evaluate Ratios Involving Unit Conversion

Betty and Mary participated in a 400 m sprint. Betty finished it in 1 min 40 sec while Mary finished it in 2 min 15 sec. What is the ratio of Mary's time to Betty's time?

1. Determine the Scale of a Map (Ratio)

The distance between two cities on a map is 4 cm. If the real distance between the cities is 28 km, what is the scale of the map?

1. A Tyrannosaurus (a dinosaur) is 12.3 m in length. If a model was built using the ratio 1:15, what is the length of the model?
1. Analyze Ratios of 3 Objects

A bank wants to maintain the managers, analysts and tellers in the ratio 2:5:18. If 15 analysts were hired, how many managers and tellers should they hire?

###### Topic Notes
In this lesson, we will learn:
• Understanding Ratio Tables
• Part-to-part Ratio Vs. Part-to-whole Ratio
• Evaluate Ratios Involving Unit Conversion
• Determine the Scale of a Map (Ratio)
• Analyze Ratios of 3 Objects

Notes:
• A ratio shows the relative values of two or more objects
• A punctuation mark colon (:) or the word "to" is used to separate the values.
• A ratio can be expressed as a fraction, which can be further converted to a decimal or a percentage.
• A ratio should always be in its simplest form (no common factors).
• The values in a ratio should always be integers if possible.
• A ratio can be scaled up/down by multiplying/dividing the ratio numbers by the same value. This process is called scaling, and the value used for scaling is called the scale factor.
• There are two types of ratio:
• Part-to-part (comparing one part to another)
• Part-to-whole (comparing one part to the whole)