standard_description: Understand the concept of a unit rate a/b associated with a ratio a:b with b ≠0, and use rate language in the context of a ratio relationship. For example, “This recipe has a ratio of 3 cups of flour to 4 cups of sugar, so there is 3/4 cup of flour for each cup of sugar.” “We paid $75 for 15 hamburgers, which is a rate of $5 per hamburger.” (Expectations for unit rates in this grade are limited to non-complex fractions.)
problem_activity: Task
2 bottles of water cost $5.00.
Fill in the table that shows the costs for 4, 6, and 8 bottles. Find the cost for a single bottle in each case.
{"table": [{"thead": [{"tr": [{"th": [{"_attributes": {"scope": "col"}, "_value": "Number of bottles"}, {"_attributes": {"scope": "col"}, "_value": "Cost (\\$)"}, {"_attributes": {"scope": "col"}, "_value": "Cost per bottle"}]}]}], "tbody": [{"tr": [{"td": [{"_value": "$$2$$"}, {"_value": "$$5$$"}, {}]}, {"td": [{"_value": "$$4$$"}, {}, {}]}, {"td": [{"_value": "$$6$$"}, {}, {}]}, {"td": [{"_value": "$$8$$"}, {}, {}]}]}]}]}
5 granola bars cost $4.00
Fill in the table that shows the costs for 10, 15, and 20 granola bars. Find the cost for a single granola bar in each case.
{"table": [{"thead": [{"tr": [{"th": [{"_attributes": {"scope": "col"}, "_value": "Number of granola bars"}, {"_attributes": {"scope": "col"}, "_value": "Cost (\\$)"}, {"_attributes": {"scope": "col"}, "_value": "Cost per bar"}]}]}], "tbody": [{"tr": [{"td": [{"_value": "$$5$$"}, {"_value": "$$4$$"}, {}]}, {"td": [{"_value": "$$10$$"}, {}, {}]}, {"td": [{"_value": "$$15$$"}, {}, {}]}, {"td": [{"_value": "$$20$$"}, {}, {}]}]}]}]}
Explain why if you can buy $a$ items for $b$ dollars, or buy $2a$ items for $2b$ dollars, the cost per item is the same in either case.


aligns: yes