Step: 1

Let n be the total number of girls in the school.

Step: 2

[Write a proportion in terms of Number of boys Number of girls .]

Step: 3

5 × n = 4 × 350

[Write the cross products.]

Step: 4

5n = 1400

[Multiply.]

Step: 5

[Divide both sides by 5.]

Step: 6

Step: 7

The total number of girls in the school is 280.

Correct Answer is : 280

Step: 1

Let d be the distance in kilometers.

Step: 2

[Write proportion in miles kilometers .]

Step: 3

0.62 × d = 1 × 1550

[Write cross products.]

Step: 4

0.62d = 1550

[Multiply.]

Step: 5

[Divide both sides by 0.62.]

Step: 6

Step: 7

The flying distance between City - A and City - B is 2500 km.

Correct Answer is : 2500 km

Step: 1

Let n be the number of hours the Concorde takes to circle the Earth.

Step: 2

[Write a proportion.]

Step: 3

3630 x n = 25168 x 3.75

[Write the cross products.]

Step: 4

3630n = 94380

[Multiply.]

Step: 5

[Divide both sides by 3630.]

Step: 6

Step: 7

The Concorde would take 26 hours to circle the Earth.

Correct Answer is : 26 hours

Step: 1

Let n be the capacity of the smaller can (in gallons).

Step: 2

[Write a proportion.]

Step: 3

4 × 25 = 5 × n

[Write the cross products.]

Step: 4

100 = 5n

[Multiply.]

Step: 5

[Divide both sides by 5.]

Step: 6

20 = n

[Simplify.]

Step: 7

The capacity of the smaller can is 20 gallons.

Correct Answer is : 20 gallons

Step: 1

The distance covered by the tortoise in one hour = 1 5 = 0.2 mi.

[Since Distance = Speed Time .]

Step: 2

Let n be the number of miles that hare can cover in one hour.

Step: 3

[Write a proportion.]

Step: 4

10 × 0.2 = 1 × n

[Write the cross products.]

Step: 5

2 = n

[Multiply.]

Step: 6

Hare can cover 2 mi in one hour.

Correct Answer is : 2 mi

Step: 1

Let h be the average fuel mileage of bike (in mi/L).

Step: 2

[Write a proportion.]

Step: 3

1 × h = 3 × 11

[Write the cross products.]

Step: 4

[Simplify.]

Step: 5

The average mileage of bike is 33 mi/L.

Correct Answer is : 33 mi/L

Step: 1

Let t be the number of hours of walk required to lose 1 lb of weight.

Step: 2

[Write a proportion.]

Step: 3

0.08 × t = 3 × 1

[Write the cross products.]

Step: 4

0.08t = 3

[Multiply.]

Step: 5

[Divide each side by 0.08.]

Step: 6

[Simplify.]

Step: 7

You should walk about 37.5 hours to lose 3 lb of weight.

Correct Answer is : 37.5 hours

Step: 1

Let n be the measure of foot size of Danielle in centimeters.

Step: 2

[Write a proportion.]

Step: 3

2 × n = 5 × 3.5

[Write the cross products.]

Step: 4

2n = 17.5

[Multiply.]

Step: 5

[Divide both sides by 2.]

Step: 6

Step: 7

The size of Danielle's foot is 8.75 cm.

Correct Answer is : 8.75

Step: 1

Let n be the diameter of the model represented as the Earth (in inches).

Step: 2

7 feet = 7 × 12 = 84 in.

[Convert feet into inches.]

Step: 3

[Write a proportion.]

Step: 4

109 × n = 84 × 1

[Write the cross products.]

Step: 5

109n = 84

[Multiply.]

Step: 6

[Divide both sides by 109.]

Step: 7

Step: 8

Therefore the diameter of the model represented as the Earth is about 0.7 in.

Correct Answer is : 0.7 in.

Step: 1

Let n be the number of liters of water.

Step: 2

[Write a proportion in terms of milk/water.]

Step: 3

4 × n = 3 × 16

[Write the cross products.]

Step: 4

4n = 48

[Multiply.]

Step: 5

[Divide both sides by 4.]

Step: 6

Step: 7

12 liters of water was mixed with 16 liters of milk.

Correct Answer is : 12 liters

Step: 1

Let r be the increase in radius of the snowball (in inches).

Step: 2

[Write the proportion in terms of feet/inches.]

Step: 3

10 × r = 1 × 40

[Write the cross products.]

Step: 4

10r = 40

[Multiply.]

Step: 5

[Divide both sides by 10.]

Step: 6

Step: 7

The radius increases by 4 in.

Step: 8

The final radius of the snowball = Initial radius + Increase in radius = 6 + 4 = 10 in.

Step: 9

So, the radius of the snowball after it travels 40 ft is 10 in.

Correct Answer is : 10 in.

Step: 1

Let n be the weight of Emily on moon (in lb).

Step: 2

[Write a proportion in terms of Weight on Earth Weight on Moon .]

Step: 3

120 × n = 20 × 48

[Write the cross products.]

Step: 4

120n = 960

[Multiply.]

Step: 5

[Divide both sides by 120.]

Step: 6

Step: 7

Emily would weigh 8 lb on Moon.

Correct Answer is : 8 lb

Step: 1

Let y be the number of days Nathan takes to consume 36 liters of water.

Step: 2

4y = 36

[Write the linear equation.]

Step: 3

[Divide each side by 4.]

Step: 4

[Simplify.]

Step: 5

Nathan takes 9 days to consume 36 liters of water.

Correct Answer is : 9

Step: 1

The distance covered by the tortoise in one hour = 1 2 = 0.5 mi.

[Since Distance = Speed Time .]

Step: 2

Let n be the number of miles that hare can cover in one hour.

Step: 3

[Write a proportion.]

Step: 4

3 × 0.5 = 1 × n

[Write the cross products.]

Step: 5

1.5 = n

[Multiply.]

Step: 6

Hare can cover 1.5 mi in one hour.

Correct Answer is : 1.5 mi

Step: 1

Let m be the distance between the two cities (in miles).

Step: 2

[Write a proportion.]

Step: 3

1 × m = 80 × 6.3

[Write the cross products.]

Step: 4

[Multiply.]

Step: 5

The distance between Rupert and Rushville is 504 miles.

Correct Answer is : 504 miles

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- Proportion