medium · GMAT Quant
Machine A alone fills a tank in 6 hours. Machine B alone fills the same tank in 10 hours. Machine B begins filling the tank alone; after B has worked alone for 2 hours, Machine A joins and the two work together until the tank is completely full.
How many hours after Machine B starts is the tank completely full?
- 4
- 4.5
- 5
- 5.5
- 6
Sign up free to see the explanation and track your rank →
More GMAT Quant practice
- Including both endpoints, how many distinct integer price points are in this range?
- Which of the following expressions must result in a positive value?
- Which property of arithmetic justifies that first step?
- Which of the following must also be an even integer?
- Which of the following inequalities correctly represents this range?
- Which of the following includes the number 0?
- How many unique meal combinations can a customer create?
- What is the probability that the lightbulb is functional?