Question

Please help with 1-9 43 points

Answer 1

Remark

I'll do two from each group, leaving you with 1. I just leave the answer for the one I don't do or a hint it it is long. That's more than we are instructed to do (which is three parts per posted question).

One

Two ratios form a proportion because they both equal the same thing when you reduce them to the point where the ratios are prime to each other.

3/4 = 12/16

3/4 can't be reduced any further. When both 12 and 16 are divided by 4, the result is 3/4

Two

Formula

Sale Price/Original Price = 3/4

Solve

Sale Price / 64 = 3/4           Multiply both sides by 64

Sale Price = (3/4)*64

Sale Price = 48

Three

682 Trillion atoms of hydrogen.

Four

Formula

rotations / 40 seconds = rotations / second

Solve

2000 / 40 seconds = rotations / 1 second    Just divide

50 rotations/1 second = rotations / second.

Five

Formula

Herd of cows / Total pounds of milk = 1 cow / pounds of milk

Given

Herd = 12

pounds total = 224998

Solve

12/224998 = 1 / x             Cross multiply

12x = 224998

x = 18750 pounds of milk for 1 cow.

Six

0.5 m in 1 second.

Seven

Formula

Pages / hour = pages / minute

pages / hour = 4.5

1 hour = 60 minutes.

Solve

4.5 / 1 hour. But 1 hour = 60 min

4.5 pages / 60 min = 0.075 pages per minute.

Note this is not a true proportion. You just have to know how it is done.

Eight

This is also not a true proportion. The best way to do this is called unit analysis.

$\dfrac{18feet}{2seconds} * \dfrac{1 mile}{5280 feet}\dfrac{3600sec}{1hour}$

Each set of units on the right will cancel with a set of units on the left until all that you area left with is miles / hour. Then just multiply the numerator numbers together and denominator numbers together.

numerator: 18 * 1 * 3600 = 64800

denominator: 2 * 5280 * 1 = 10560

Now divide the numerator by the denominator.

answer: numerator/denominator = 64800/10560 = 6.14 miles per hour.

Nine                                              

Note: there are 1760 yards in a mile.

1 gallon will take you 32000 yards or 18 miles. Do this the same way eight was done.

Answer 2

Answer: 1 gallon will take you 32000 yards or 18 miles. Do this the same way eight was done.