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kodGreya [7K]
3 years ago
13

How to solve this problem?

Mathematics
1 answer:
valentinak56 [21]3 years ago
6 0

Very nice handwriting but the math and English are confusing.

Let's assume we're told

\displaystyle 45 = \sum_{i=1}^9 (x_i - 10)^2

The subscript is important.

I think we're told the similar sum with 11 gives the smallest possible value for the sum. This is a rather cagey way of telling us 11 is the mean of the nine points. The mean is the number which minimizes the sum of squared deviations.

\displaystyle 45 = \sum_{i=1}^9 (x_i - 10)^2 = \sum x_i^2 - 20 \sum x_i + 9(100)

\displaystyle  \sum x_i^2=  20 \sum x_i  - 900

If 11 is the mean, the sum of the points is 9(11)=99.

\displaystyle  \sum x_i^2=  20 (99)  - 900 = 1080

Answer: 1080

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Step-by-step explanation:

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Greatest common factor of the numbers 12,40 and 60 is
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The greatest common factor between any list of numbers is the biggest multiple that they all share.
For example, 5, 35 and 50 all share 5 as the biggest common factor, making 5 the greatest common factor.

Now that we have our example and definition out of the way, let's make out the factors.

12:
1 x 12
2 x 6
3 x 4

40:
1 x 40
2 x 20
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5 x 8

60:
1 x 60
2 x 30
3 x 20
4 x 15
5 x 12
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Now that we have our factors, let's look for the biggest number that they have in common.

They all share 4 as the biggest number.

Your GCF (Greatest Common Factor) is 4.

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B) 158.3ft

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A) Having a collinear line makes the triangles similar, and because of their collinear line they are both right triangles.

B) The question tells you DE is 103 ft. You take 76ft and Square it giving you 5776ft You then take 103 and square it giving you 10609ft adding them together gives you 16385ft you take the square root of it and it gives you the hypotenuse of triangle CDE. To get the hypotenuse of triangle ABC you take The expression (AB/DE)=(BC/CD)=(AC/EC) step one (AB/DE)=(94ft/76ft)=AC/DE) step two (103ft/127ft)=(94ft/76ft)=(AC/DE) third step (103ft/127ft)=(94ft/76ft)=(128ft/158.3)

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