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1 year ago

At summer camp the ratio of boys to girls was 7:2 If there were 21 boys how many girls were there?

1 answer:

3 0

$Ratio:\\7:2\\\\
7x-number\ of\ boys\\2x-number\ of\ boys\\\\
7x=21\ \ \ |:7\\
x=3\\\\
2x=2*3=6\\
Number\ of\ girls\ is\ equal\ to\ 6.$

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Answer:

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$P(x < 8.2) =0.9772 = 97.72\%$

This statement can be made with a level of confidence of 97.72%.

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2 years ago

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Answer:

Part a) You could build 5 copies of the flower pattern

Part b) You would have 40 red trapezoids left over

Step-by-step explanation:

The complete question in the attached figure

Part a)

Let

x -----> the number of yellow hexagons

y ----> the number of red trapezoids

z ----> the number of green triangles

we know that

The flower pattern has the following ratios

$\frac{x}{y}=\frac{6}{2} ---->\frac{x}{y}=3 ----> \text {equation A}$

$\frac{x}{z}=\frac{6}{9} -->\frac{x}{z}=\frac{2}{3} --> \text {equation B}$

$\frac{y}{z}=\frac{2}{9} ------> \text {equation C}$

Find out how many copies of this flower pattern could you build if you had 30 yellow hexagons,50 red trapezoids, and 60 green triangles

1) For x=30

Divide 30 by 6 (remember that in one pattern there are 6 yellow hexagons)

$30/6=5\ copies$

Verify the quantity of y needed and the quantity of z needed

Find the value of y

$\frac{30}{y}=3 ---->y=30/3=10\\$

10 < 50 ----> is ok

Find the value of z

$\frac{30}{z}=\frac{2}{3} ---> z=30*3/2=45$

45<60 --->is ok

2) For y=50

Divide 50 by 2 (remember that in one pattern there are 2 red trapezoids)

$50/2=25\ copies$

Verify the quantity of x needed and the quantity of z needed

Find the value of x

$\frac{x}{50}=3 ---->x=50*3=150$

150 > 30 ----> is not ok

3) For z=60

Divide 60 by 9 (remember that in one pattern there are 9 green triangles)

60/9=6.7 copies

Round down

6 copies -----> 6(9)=54 green triangles

Verify the quantity of x needed and the quantity of y needed

Find the value of x

$\frac{x}{54}=\frac{2}{3} ---> z=54*2/3=36$

36> 30 --->is not ok

therefore

You could build 5 copies of the flower pattern

Part b)

we know that

x:y:z=6:2:9

If you build 5 copies

1) You would use 5*6=30 yellow hexagons and you would have 0 hexagons left over

2) You would use 5*2=10 red trapezoids and you would have (50-10=40) trapezoids left over

3) You would use 5*9=45 green triangles and you would have (60-45=15) triangles left over

therefore

You would have 40 red trapezoids left over

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1 year ago