Deck 7: Ratio and Proportion

Question 1

Simplify the following ratio.

Answer 1

6:1

Question 2

Simplify the following ratio.

Answer 2

5:1

Question 3

Solve this proportion.

Answer 3

8.4

Question 4

Solve this proportion. A copper wire 750 feet long has a resistance of 1.893 ohms. How long is a copper wire of the same diameter whose resistance is 3.156 ohms? Express the answer to the nearer tenth.

Question 5

Solve this proportion.

Question 6

Solve this proportion. Four workers complete a certain electrical job in 120 hours. How long will it take three workers working at the same rate to do the same type of job?

Question 7

Solve this proportion.

Question 8

Solve this proportion.

Question 9

Solve this proportion. If a piece of cable 160 feet long costs $60, what will 500 feet of the same cable cost?

Question 10

Solve this proportion.

Question 11

Solve this proportion.

Question 12

Solve this proportion.

Question 13

Simplify the following ratio.

Question 14

Simplify the following ratio.

Question 15

Solve this proportion. A wire 2,725 feet long and 85 mills in diameter has a resistance of 0.372 ohm. Find to the nearer thousandth the resistance of 3,600 feet of the same wire.

Question 16

Simplify the following ratio. 12:3

Question 17

Solve this proportion.

Question 18

Simplify the following ratio. 25:10

Question 19

Simplify the following ratio.

Question 20

Solve this proportion. A wire 1,325 feet long has a resistance of 0.65 ohm. What is the resistance to the nearer hundredth of one mile of the same wire?

Question 21

Find the inverse of each ratio. 5:112

Question 22

Solve this proportion. An electrical repair team of 6 electricians completes a job in 3 hours. How long in hours should it take 2 electricians working at the same rate to do the same amount of work?

Question 23

It costs $120 for 10 feet of 4" conduit. What will it cost for 50 feet of 4" conduit?

Question 24

The answer is in this format: 5:9. If it takes one electrician 18 hours to wire a house and a second electrician 45 hours to wire a similar house, what is the ratio of the second electrician's to the first electrician's time?

Question 25

Find the inverse of each ratio. 5:2

Question 26

The answer is in this format: 5:9. What is the ratio of the speed of one motor turning at 1,750 rpm to the speed of a second motor turning at 3,500 rpm?

Question 27

Solve this proportion. An electrical repair team of 12 workers completes a job in 288 hours. How long should it take 9 workers working at the same rate to do the same amount of work?

Question 28

Find the inverse of each ratio. 7:8

Question 29

If an engine is operating at 1,350 revolutions per minute at 25 mph, how fast will the engine be operating at 65 mph?

Question 30

Find the inverse of each ratio.

Question 31

Solve this proportion. A wire 100 feet long has a resistance of 800 ohms. How long is a copper wire of the same area whose resistance is 600 ohms, in feet?

Question 32

A 1-foot ruler held perpendicular to the ground casts a shadow 8 inches long. At the same time, a pole casts a shadow 22 feet 4 inches long. What is the height of the pole as a decimal number?

Question 33

Solve this proportion. A new "dry pump" is capable of delivering 100 gallons of liquid per minute. How long in hours will it take the pump to deliver 6,000 gallons?

Question 34

If 16.2 gallons of fuel are used to drive 435 miles, how many gallons are needed to drive 1,680 miles? Carry the answer to one decimal place.

Question 35

A differential gear has 48 teeth and the drive pinion has 14. What is the final drive-gear ratio?

Question 36

The answer is in this format: 5:9. Find the ratio of 200 turns of the primary coil to 800 turns of the secondary coil.

Question 37

A technician was getting paid $12.80 an hour. The boss decided to give him a 5% raise. What was his new hourly wage?