some QR word problem tips

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bryantje

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Those of you worried about word problems on the QR section should believe the hype. Algebra, exponents, and trig/geometry are on there, but you should go through and do them first to maximize the number of questions you can do in the least amount of time. The KEY to this section is being able to do word problems quickly.

Fortunately, I have some good advice. The GMAT Original Guide, available at most bookstores, has a section FULL of practice word problems very very similar to the kind you will see on the DAT. Probabilty, conversions, rate/distance problems, etc that take longer to crank out can be practiced extensively with this book. The explanations to each problem are also very helpful if you get stuck.

The more practice you get for word problems, the less chance there is of fatigue or lack of time will become. Take it from someone who didn't heed his own advice!
 
Thanks for the advice, can you help me with this problem? Cubby and Annette are 60 miles apart. Cubby begins bicycling toward Annette at 11 1/2 mph. At the same
time, Annette starts walking toward Cubby at 3 1/2 mph. In how many hours will the pair meet?
A. 4
B. 5
C. 7 1/2
D. 8
E. 15

Thank you!!
 
Wouldn't it be 4 hours? 11.5+3.5=15 miles closer per hour. Then 60 miles ÷ 15 mph = 4 hours right?

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Thanks for the advice, can you help me with this problem? Cubby and Annette are 60 miles apart. Cubby begins bicycling toward Annette at 11 1/2 mph. At the same
time, Annette starts walking toward Cubby at 3 1/2 mph. In how many hours will the pair meet?
A. 4
B. 5
C. 7 1/2
D. 8
E. 15

Thank you!!

You have to use the d = r x t formula to use this problem.

Cubby ----------------------Annette

they are apart 60 miles, and they are coming to each other, so you have to add the

rate of both people since they are going toward the same direction.

Anette's rate is 23/2 mph if you convert the 11 1/2, and Cubby's will be 7/3 mph

According to the distance formula, you can rearrange to d/r = t

Then, 60/ ((23/2) + (7/3)) Then, you will get 4 hours to meet each other.
Hope, this works.
 
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these ones are always fun.

- you know speed is just distance over time, so we start with s=d/t
- we can then rearrange and say d=(s)(t) or d(cubby)=s(cubby) x time and same for annette
- we also know that no matter how long it takes for them to meet, the sum of the distances they travel will equal how far from each other they started, so d(cubby) + d(ann) = 60
- subbing: s(cubby) x time + s(ann) x time = 60
- factor out time: time x [s(cubby) + s(ann)] = 60

solve for "time" and you should get 4hrs

also, solid necrobump. maybe next time you can just start a new thread.

edit: ^^^ faaaast sdn
 
Can anyone verify that the GMAT book op is talking about is legit? I would like some detailed walk throughs and practice problems for QR..
 
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