Stuck? Start here. Read the steps, try the problem, then check your answer.
I can…
I can write and describe a ratio that compares two quantities.
Key words
Understand Ratios — Use a ratio to compare two quantities by division.
Ratio — A way to compare two amounts, like 3 to 2.
Comparison — Looking at two or more amounts to see how they are related.
Part-to-part — A ratio comparing one part of a group to another part.
Part-to-whole — A ratio comparing one part to the whole group.
Colon notation — Writing a ratio with two dots between the numbers, like 3:2.
Tape diagram — A bar cut into equal parts that shows how two amounts in a ratio compare, and how they make up the whole.
Double number line — Two number lines lined up so matching tick marks show the two quantities in a ratio at the same time.
Term — One of the two numbers in a ratio.
Simplest form — A ratio whose terms have been divided by the largest number that divides both.
Total parts — The two terms of a ratio added together.
Steps
Chef Reyes uses 3 cups of apple juice for every 2 cups of sparkling water.
I am comparing two amounts: apple juice and sparkling water.
I write apple juice to sparkling water, in that order, as 3 to 2, or 3:2.
I can also draw the ratio. On a tape diagram I give apple juice 3 equal parts and sparkling water 2 equal parts, so one batch is 5 parts in all.
Those same 5 parts show a second ratio: apple juice to the whole fruit drink is 3 to 5.
On a double number line I line the two amounts up: 5 cups of fruit drink pairs with 3 cups of apple juice, and 10 cups of fruit drink pairs with 6 cups of apple juice.
Try it
A garden has 7 tulips and 4 daisies. What is the ratio of daisies to all the flowers in the garden?
Check your answer
4:11
Total flowers = 7 + 4 = 11. The ratio of daisies to all the flowers is 4:11.
Sentence starter
I know ___ because ___.
Goal: I can explain a comparison using the words ratio, part-to-part, part-to-whole, and colon notation.