These word problems may involve percentages, rate-time-distance, consecutive integers, ages, work rate, coins, divisibility, factors, multiples, sequences, and equation setup.
Practice questions
- Kyra and Sage, working together, can paint a room in 5 hours. If Melora helps Kyra and Sage paint the room, the three of them can paint the room in 4 hours. What amount of time (in hours) would it take Melora, working alone, to paint the room?
A. 6 B. 8 C. 10 D. 15 E. 20
- Ninety percent of a large field is cleared for planting. Of the cleared land, 50 percent is planted with blueberry plants and 40 percent is planted with strawberry plants. If the remaining 360 acres of cleared land is planted with gooseberry plants, what is the size, in acres, of the original field?
A. 2,916 B. 3,240 C. 3,600 D. 4,000 E. 8,000
Answers and explanations
- The correct answer is E.
Let t = the time (in hours) it would take Melora, working alone, to paint the room. The portion of the room Melora, working alone, can paint in one hour is 1/t. The portion of the room Kyra and Sage, working together, can paint in one hour is 1/5. The portion of the room the three of them, working together, can paint in one hour is 1/4. Therefore,
Solve the equation:
Melora would take 20 hours, working alone, to paint the room.
- The correct answer is D.
Let A = the size (in acres) of the original field. Then
The percent of the cleared land planted in gooseberry plants is
Solve the equation:
The size of the original field is 4,000 acres.