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Westkost [7]
2 years ago
10

Why do you cross-multiply when you solve proportions?

Mathematics
2 answers:
olga55 [171]2 years ago
4 0

Answer:

Step-by-step explanation:

since the cross multiples are equal, you find a product and use the inverse operation as you would in an equation

Example 4 is to 36 as 3 is to X: 4/36 = 3/X --> 4*X = 3*36. Divide both sides by 4, to solve for X = 27.

is over of = percent of 100

is/of=%/100

What is 10% of 40.

is = x

x/40 = 10/100

cross mulitply 40*10= 400/100=4 x=4

0

1

2

Dmitriy789 [7]2 years ago
3 0
When students cross multiply while solving a proportion, they are really multiplying both sides of the equation by the products of the two denominators. What happens is that each denominator cancels one of the factors on each side, so that it seems as if you have just crossed multiplied

Hope this helps!
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Plz answer ASAP need help
Aleks04 [339]

Answer:

4 hours

Step-by-step explanation:

Let the number of hours = x.

Jay reads 55 pages per hour, so in x hours, he reads 55x pages.

After reading for x hours, he has 278 - 55x pages left to read.

Odhran reads 45 pages per hour, so in x hours, he reads 45x pages.

After reading for x hours, he has 238 - 45x pages left to read.

Since we want to know when they have the same number of pages left, we set the expressions equal and solve for x.

278 - 55x = 238 - 45x

Add 45x to both sides.

278 - 10x = 238

Subtract 278 from both sides.

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6 0
3 years ago
Factor the following expression <br> 10x^5+5x^3-14x^2-7-
Tatiana [17]

Answer:

C. (5x^3-7)(2x^2+1)

Step-by-step explanation:

Given expression is,

10x^5+5x^3-14x^2-7

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=2x^2(5x^3-7)+5x^3-7     (Taking 2x^3 common from first two terms )

=(5x^3-7)(2x^2+1)      (Taking 5x^3-7 common from both terms)

\implies 10x^5+5x^3-14x^2-7=(5x^3-7)(2x^2+1)

Hence, Option C is correct

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The store bought a pair of shoes for $50, and sold it for $80.What percentage was the mark up
Charra [1.4K]
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Mars2501 [29]

Answer:

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insens350 [35]

Answer:

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Step-by-step explanation:

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5 0
2 years ago
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