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3 years ago

1. Justin’s car can travel 77.5 miles using 3.1 gallons of gas.

2 answers:

Nadusha1986 [10]3 years ago

5 0

Distance/fuel=ratio 77.5/3.1 is proportional to xdistance/8.2 77.5/3.1=x/8.2 multiply both sides by (3.1*8.2) 635.5=3.1x divide both sides by 3.1 205=x 205 miles 2. easy peasy one way is boys+15=girls boys+girls=85 boys+boys+15=85 minus 15 2boys=70 divide 2 boys=35

lisabon 2012 [21]3 years ago

4 0

1) Write this as a ratio...

77.5 miles / 3.1 gallons = x miles / 8.2 gallons

Solve for x... multiply by 8.2 gallons on both sides (that cancels it on the right) side of the equation.

8.2 gallons * 77.5 miles / 3.1 gallons = x
635.5/ 3.1 = x
211.83 miles = x

Justin travels 211.83 miles on 8.2 gallons of gas

2) If we let boys = b, then girls has to be b + 15 (since there are 15 more girls than boys). Now together there are 85 members of the band so... boys + girls = 85 and since girls is b + 15, then...

b + b+15 = 85

Now solve for b. First combine like terms...

2b + 15 = 85

Now subtract 15 from each side (cancels the 15 on the left)

2b + 15 - 15 = 85 - 15
2b = 70

Now divide each side by 2 (cancels 2 on the left)

2b / 2 = 70 / 2
b = 35

So there are 35 boys in the band.

Just FYI, that also means there are 35+15 = 50 girls. Just so happens that 50 + 35 = 85 so our work checks!

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Answer:

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Step-by-step explanation:

For the question to make any sense, we need to add parentheses.

... x^(2a-1)/y^(3b+4) × x^(7b-4)/y^(10-a) = x^24/y^19

Equating exponents, we have ...

... (2a-1) + (7b-4) = 24 . . . . exponent of x in the product

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Simplifying these two equations, we get

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... a -3b = -5

By Cramer's rule, ...

... a = (7·(-5) -(-3·29)/(7·1 -(-3·2)) = 52/13 = 4

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<em>More about Cramer's Rule</em>

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Once you recognize the pattern in the products, the formula is not difficult to remember.

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Licemer1 [7]

Answer:

6/7 > 1/2

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Step-by-step explanation:

Suki's distance = 6/7 miles

Compare with bechmark 1/2

6/7 and 1/2

Make the denominators same

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12/14 and 7/14

12/14 is greater than 7/14

12/14 > 7/14

Therefore, 6/7 > 1/2

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Compare with bechmark 1/2

1/3 and 1/2

Make the denominators same

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2/6 is less than 3/6

2/6 < 3/6

Therefore,

1/3 < 1/2

Compare Suki's distance with Clarie

compare 6/7 and 1/3

Make the denominators same

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