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The actual distance between Emerald City and Diamond Bluff is: \(\dfrac{42}{3,5}\cdot2,75=33\left(miles\right)\)
ANSWER: 33 miles
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The height of the sixth bounce is: \(5\cdot80\%\cdot80\%\cdot80\%\cdot80\%\cdot80\%=1,6384\approx1,6\left(ft\right)\)
ANSWER: 1,6 ft
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Because the head size is 15% then the total size of body and foot is: 100% - 15% = 85%
The percentage of body size is: \(\dfrac{85}{\left(5+7\right)}\cdot5=\dfrac{425}{12}\approx35\%\)
P/s: I can't understand of the ratio 1:10
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The boy has covered only two-fifth way => The total speed of the girl and the moving walkway is: \(\dfrac{5}{2}\)
So the ratio of the walkway's rate to the girl's rate (sililar to the boy's rate) is: \(\dfrac{5}{2}-1=\dfrac{3}{2}=3:2\)
ANSWER: \(3:2\)
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The fraction is: \(\left(1-\dfrac{2}{5}\right):2=\dfrac{3}{10}\)
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There are: \(\left(1992-2\right):2+1=996\left(numbers\right)\)
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We arrange the numbers of dollars: 5-6-8-10-10-14-18-18-22-22-25-27-27-30-30-31-32-41-42-43-53
So the median of the dollar amount is: 25 dollars
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The ratio of the area of the second and the first pasture is: \(\left(8:2\right)^2=16\)
So the area of the second pasture is: \(25\cdot16=400\left(hectares\right)\)
ANSWER: 400 hectares
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There are: \(9-2=7\left(students\right)\) in orchestra and chorus
There are: \(4-2=2\left(students\right)\) in band and orchestra
So the students are in orchesta only is: \(21-\left(7+2+2\right)=10\left(students\right)\)
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The ratio of triangle WXY to triangle ABC is: \(4:18=\dfrac{2}{9}\)
The base of triangle ABC is: \(243:18\cdot2=27\left(cm\right)\)
So the length of segment WY (the base of triangle WXY) is: \(27\cdot\dfrac{2}{9}=6\left(cm\right)\)
ANSWER: 6cm
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Because the diagonal of the rectangle seperates the rectangle into 2 similar triangles
=> The answer is: \(\sqrt{18^2+24^2}\cdot2=\sqrt{324+576}\cdot2=\sqrt{900}\cdot2=30\cdot2=60\left(m\right)\)
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We call: t-the time Tim drove
=> Tim drove at 30t mi.
=> Kim drove at: \(40\cdot3t=120t\)
=> \(t=225:\left(30+120\right)=1,5\)
So Tim drove: \(1,5\cdot30=45\left(mi\right)\)
ANSWER: 45 mi
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From 101 to 199 (except from 130 to 139) she needs: \(1\cdot9=9\left(sers\right)\)
From 130 to 139 she needs: \(1\cdot10+1=11\left(sers\right)\)
From 200 to 250 (except from 230 to 239) she needs: \(1\cdot4=4\left(sers\right)\)
From 230 to 239 she needs: \(1\cdot10+1=11\left(sers\right)\)
So she need to purchase: \(11+4+11=26\left(sers\right)\)
ANSWER: 26 sers
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We have: 3x + 3 = 2x + 7
=> 3x - 2x = 7 - 3
=> x = 4
So the value of x is: 4
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The range of the set is: 16-4 = 12
The mean of the set is: \(\left(4+5+7+7+8+8+8+9+16\right):9=8\)
Because 12 > 8 <=> The positive difference between the range and the mean is: 12-8 = 4
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The average speed which Blake traveled is: \(\dfrac{117}{2,25}=52\) (mi/h)
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There are: \(1140-1140\cdot\dfrac{2}{3}=380\left(students\right)\) will not attend in the Spring Festival
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He made: \(18\cdot60\%=10,8\) shots.
P/s: The number of shots mustn't be odd.
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We have: \(\dfrac{a}{6}=\dfrac{b}{3}=\dfrac{c}{12}=\dfrac{a-b+c}{6-3+12}=\dfrac{30}{15}=2\)
=> \(\dfrac{a}{6}=2\) <=> \(a=6\cdot2=12\)
=> \(\dfrac{b}{3}=2\) <=> \(b=3\cdot2=6\)
=> \(\dfrac{c}{12}=2\) <=> \(c=12\cdot2=24\)
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We have: \(\dfrac{a}{3}=\dfrac{b}{4}=\dfrac{a+b}{3+4}=\dfrac{14}{7}=2\)
=> \(\dfrac{a}{3}=2\) <=> \(a=3\cdot2=6\)
=> \(\dfrac{b}{4}=2\) <=> \(b=4\cdot2=8\)