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3 years ago

(05.02 MC)

Mathematics

1 answer:

Elanso [62]3 years ago

4 0

His work should have looked like this.

2x + y = 5
x − 2y = 10

y = 5 − 2x
x − 2(5 − 2x) = 10
x − 10 + 4x = 10
5x − 10 = 10 When he added in both sides, he subtracted 10 from 10,
5x = 20 instead of adding 10 from 10 to make 20.
x = 4
2(4) + y = 5
8 + y = 5

y = -3

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Weiming, Joyce and Siti divide cookies to sell in a ratio of 5: 12: 9. After Weiming sold 28 cookies, the ratio becomes 1: 8: 6.

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Answer:

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Step-by-step explanation:

From the question,

Let the total cookies in the first place be x cookies.

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Therefore,

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The park and movie theater are 3.4 inches apart on a map. If the map has a scale of 0.25 inch = 5 miles, find the actual distanc

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Step-by-step explanation:

The given is,

Park and movie theater are 3.4 inches apart

Map has a scale of 0.25 inch = 5 miles

Step:1

Formula to calculate the number of scales for distance between park and theater,

$= \frac{Distance in map}{Scale value of map}$

$= \frac{3.4}{0.25}$

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number of scales for distance between park and theater = 13.6

Step:2

Formula to convert distance inches to miles

$= Number of scale$ × $Equivalent value inches to miles$

= 13.6 × 5

= 68

Actual distance between park and theater = 68 miles

Result:

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