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GMAT · GMAT

GMAT Word Problems and Problem Solving

Rate, work, and mixture word problem setups and solving approaches tested on the GMAT quantitative section.

36 cards · basic cards · AI-written, checked twice. Edit anything.

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What is the fundamental formula relating distance, rate, and time?
Distance = Rate × Time
If two people travel toward each other, how do you find their relative speed?
Add their individual speeds together
If two people travel in the same direction and one is faster, what is the relative speed?
Subtract the slower speed from the faster speed
In work problems, what does a work rate of 1/5 mean?
The worker completes one-fifth of the job in one unit of time
How do you combine work rates when two workers work together on the same job?
Add the individual work rates
If Worker A completes a job in 6 hours, what is Worker A's work rate?
1/6 of the job per hour
Workers A and B have rates of 1/4 and 1/6 per hour. What is their combined rate?
1/4 + 1/6 = 5/12 of the job per hour
If a combined work rate is 5/12 per hour, how many hours to complete the job?
12/5 hours, or 2.4 hours
What does concentration mean in a mixture problem?
The amount of solute (ingredient) divided by the total amount of solution
How do you find the amount of pure ingredient in a mixture?
Multiply the concentration by the total amount of solution
If you mix 10 liters of 40% solution with 15 liters of 60% solution, what equation sets up the pure amount in the final mixture?
0.4(10) + 0.6(15) = concentration of final mixture × 25
In a mixture problem combining two solutions, what principle ensures your equation is correct?
The total amount of pure ingredient is conserved before and after mixing
If a 200-liter tank holds a 25% solution and 50 liters are drained, what concentration remains?
Still 25% (removing solution removes solute and solvent in the same proportion)
In a work problem, if Worker A completes 1/3 of a job and Worker B completes the rest, what fraction does Worker B complete?
2/3 of the job
Two machines working together complete a job in 8 hours. If Machine A alone takes 12 hours, how long does Machine B alone take?
24 hours

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