Rates, Unit Rates, and Ratios
What are they and how do you solve them?
What are ratios?
Ratios have 3 main forms:
1. N to N
2. N : N
3. N / N
There can be "Part to Part" ratios and "Part to Whole" ratios.
For example, a family could be made up of 2 boys and 3 girls.
These two are examples of "Part to Part" ratios.
The ratio of boys to girls is 2:3, 2/3, or 2 to 3.
The ratio of girls to boys is 3:2, 3/2, or 3 to 2.
These are two examples of "Part to Whole" ratios.
The ratio of boys to the entire family is 2:5, 2/5, or 2 to 5.
The ratio of girls to the entire family is is 3:5, 3/5 or 3 to 5.
You can simplify or increase ratios.
For example, we can use the ratio 3:9.
You can simplify the ratio by dividing both numbers by 3.
If you divide them both by 3, you get 1:3.
You can also increase the ratio by multiplying it by 2, for example.
Then you would get 6:18.
What are rates?
A few examples of rates are:
1. 69¢ for 12 ounces
2. 16 feet per 4 seconds
3. $5.50 for 5 pounds of potatoes
What are unit rates?
Unit rates always have a denominator of 1.
If you wanted to find the unit rate of 16 feet per 4 seconds, you'd divide 16 by 4 and get 4 feet per second.
If you wanted to find out the unit rate of $5.50 for 5 pounds of potatoes, you would divide 5.50 by 5. The unit rate would be $1.10 per pound of potatoes.