Copyright © Swun Math Grade 8 Unit 1 Constructed Response Rubric TE

Unit 1 ∙ Constructed

ResponseSCORING RUBRIC

Unit 1 ∙ Constructed Response

Rational vs. Irrational Numbers

TASK 1: Absolute Value and Distances

Answer/Exemplar Standard Points

1a. — 13 — y = 10

—y = 23

y = — 23

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1b. —12 is an integer and a rational number. It is an integer because it

is a whole number and a negative natural number. It is also a

rational number because it is an integer that can be written as a

ratio.

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1c. Answers will vary.

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2a. Decimal Expansion: 0.375

3

Fraction: (^8)
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2b. The decimal form is a terminating, non-repeating decimal and
rational number because 0.375 has no additional or repeating
numbers after the value in the hundredths place. It is a rational
number because it is a terminating integer that can be written as a
ratio.
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3a. Mathematical Process:
x = 2.3939
100 x = 239.3939
100 x — 2.3939 = 239.3939 — 2.3939
99 x = 237
237
x = (^99)
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Explanation of Steps:
To find the solution I first set up the equation x = 2.3939. I
multiplied both sides of the equation by 100 so that the values in
each decimal place would be equal, and I can derive a whole
number after subtracting the value of x. The new equation is 100x
= 239.3939. When I subtract the value of x from both sides, I
maintain a balanced equation. The difference is a whole number.
Division is the final step
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