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vovikov84 [41]
3 years ago
11

To add 20.4 + 3.75 + 4.25, Crystal first added 3.75 and 4.25. Which property did Crystal use to add mentally?

Mathematics
1 answer:
Black_prince [1.1K]3 years ago
3 0

Answer:

A) Associative Property of Addition

Step-by-step explanation:

<u><em>Associative Property of Addition</em></u>

Let A, B and C  be any three real numbers

A+(B+C) = (A+B) + C

Given data

(20.4 + 3.75) + 4.25 =  20.4 + (3.75 + 4.25)

                                 =  20.4 + 8.0

                                =  28.4

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Answer:

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Answer:

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Step-by-step explanation:

Given

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Solving (a): Sine and Cosine A

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Cos \angle A=\frac{6cm}{10cm}

Cos \angle A=\frac{6}{10}

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In trigonometry:

Sin \theta =\frac{Opposite}{Hypotenuse} and

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Sin \angle B =\frac{AC}{BA}

Substitute values for AC and BA

Sin \angle B =\frac{6cm}{10cm}

Sin \angle B =\frac{6}{10}

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Cos \angle B=\frac{8cm}{10cm}

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Sin(53^{\circ}) =0.7986

Sin(53^{\circ}) =0.80 -- approximated

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Cos(53^{\circ}) = 0.60 -- approximated

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Sin(37^{\circ}) = 0.6018

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Hence, the upper bound is f on the interval [3,6) and g on the interval (6,9]. While the lower bound is the 0 function.

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