standard_description: Know that numbers that are not rational are called irrational. Understand informally that every number has a decimal expansion; for rational numbers show that the decimal expansion repeats eventually, and convert a decimal expansion which repeats eventually into a rational number.
problem_activity: Problem 1
Two different students solved the problem
$$1\frac9{10}+5\frac4{10}$$
below. Study their work and determine whether the strategy they used works.
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Problem 2
Two different students solved the problem
$$4\frac38-3\frac68$$
below. Study their work and determine whether the strategy they used works.
{"table": [{"_attributes": {"class": ["table"], "style": "width: 100%;"}, "tbody": [{"tr": [{"td": [{"_attributes": {"style": "text-align: center; width: 50%;"}, "strong": [{"_value": "Student C"}]}, {"_attributes": {"style": "text-align: center; width: 50%;"}, "strong": [{"_value": "Student D"}]}]}, {"td": [{"_attributes": {"style": "text-align: center;"}, "img": [{"_attributes": {"src": "https://d21royfkw9g4l6.cloudfront.net/uploads/2022/03/24/g4mathu5l14_at2a.png", "style": "width: 175px; height: 169px;"}}]}, {"_attributes": {"style": "text-align: center;"}, "img": [{"_attributes": {"src": "https://d21royfkw9g4l6.cloudfront.net/uploads/2022/03/24/g4mathu5l14_at2b.png", "style": "width: 100px; height: 206px;"}}]}]}]}]}]}
Problem 3
Solve.
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aligns: no