math semester 1 unit 2

Working together, Katherine and Marina can sand a large cabinet in 2 hours. It would take Katherine 10 hours to do the job alone. What is the value of r, the part of the job that Marina can complete in 1 hour? 0.1 0.4 0.5 0.6

0.4

Irina rode her bike to work at an average speed of 16 miles per hour. It started to rain, so she got a ride home along the same route in her coworker's car at an average speed of 27 miles per hour. If Irina's ride home in the car took 24 minutes (0.4 of an hour), how many hours was her bike ride to work, to the nearest tenth of an hour? 0.2 of an hour 0.4 of an hour 0.6 of an hour 0.7 of an hour

0.7 of an hour

Jonas jogged up the hill at an average rate of1/2of a mile per minute and then walked down the hill at an average rate of 1/16 of a mile per minute. The round trip took him 42 minutes. What is the missing value in the table that represents the distance of the trip down the hill? 1/16x 42/16-x 42-1/16x 1/16(42-x)

1/16(42-x)

Eduardo's average speed on his commute to work was 55 miles per hour. On the way home, he hit traffic and only averaged 40 miles per hour. If the round trip took him 1.25 hours, which expression represents the distance, in miles, for his trip home that is missing from the table? t - 1.25 1.25 - t 40(1.25 - t) 40(t - 1.25)

40(1.25 - t)

It takes 5 minutes to fill the sink using only the cold water. If both the hot water and the cold water are turned on, it takes 2 minutes to fill the sink. Which is the correct table that can be used to determine x, the time in minutes it takes to fill the sink using only the hot water?

C

If Judy completes a puzzle by herself, it takes her 3 hours. Working with Sal, it only takes them 2 hours. What is the missing value from the table that represents Judy's rate? r 3-r 1/3 3

1/3

If Jasper installs a floor himself, it will take him 7 hours. Working with Yolanda, it will take them 3 hours. If they work together, what is the missing value in the table that represents the part of the floor Jasper will install? 1/7(3) 1/7r 7r 7(3)

1/7(3)

Sophie and Simon are peeling a pile of potatoes for lunch in the cafeteria. Sophie can peel all the potatoes by herself in 45 minutes, while it would take Simon 30 minutes to do the job working alone. If Sophie and Simon work together to peel the potatoes, how long will it take them? 15 minutes 18 minutes 38 minutes 75 minutes

18 minutes

Mike and Jamal are 9 miles apart, and are planning to meet up. Mike is walking at an average speed of 3 miles per hour to meet Jamal. Jamal is driving at an average speed of 25 miles per hour to meet Mike. Which equation can be used to find t, the time it takes for Mike and Jamal to meet? 25t - 3t = 0 25t - 3t = 9 25t + 3t = 1 25t + 3t = 9

25t + 3t = 9

Working together, Alex and Millie can file all the papers in the file cabinets in 4 hours. It would have taken Alex 6 hours to do the job alone. What is the missing value in the table that represents the part of the papers that Alex would file if Alex and Millie worked together? 4r 4/6 6r 6/4

4/6

It takes 8 minutes for Byron to fill the kiddie pool in the backyard using only a handheld hose. When his younger sister is impatient, Byron also uses the lawn sprinkler to add water to the pool so it is filled more quickly. If the hose and sprinkler are used together, it takes 5 minutes to fill the pool. Which equation can be used to determine r, the rate in parts per minute, at which the lawn sprinkler would fill the pool if used alone? 5/8+5r=8 5/8+5r=1 5(5/8)=r 5/8=5r

5/8+5r=1

Milla and Luka are 3 kilometers apart and walking toward each other. Milla's average speed is 5 kilometers per hour and Luka's is 4 kilometers per hour. Which equation can be used to find t, the time it takes for Milla and Luka to meet? 5t + 4t = 1 5t + 4t = 3 5t - 4t = 0 5t - 4t = 3

5t + 4t = 3

Craig ran the first part of a race with an average speed of 8 miles per hour and biked the second part of a race with an average speed of 20 miles per hour. The entire two-part, 15-mile race took him 1.125 hours to complete. Which table correctly represents his rates, times, and distances for each part of the race?

A

It would take Marco 6 hours to paint a fence by himself. It would take Jaylyn 5 hours to paint the same fence by herself. Marco is creating this table to help him determine how long it would take them to paint the fence together. Which heading should be written above the first column of numbers? Rate (part/hour) Time (hours) Part of Fence Painted Distance (meters)

Rate (part/hour)