Joan walks 4 feet per second, which is half as fast as Al walks. If B

Question

Joan walks 4 feet per second, which is half as fast as Al walks. If Bob is twice as fast as Al then how far will Bob walk in a minute?

A. 960 feet
B. 480 feet
C. 240 feet
D. 60 feet
E. 16 feet

pushpitkc · Answer

Joan walks at half the speed of Al. Hence, Al walks at twice the speed(8 ft/s) Since bob walks twice as fast as al. Al's speed will be 16 ft/s or 960 ft/minute (Option A)

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0akshay0 · Answer

Bob = 2 Al = 2 Joan Al = 2*4 =8 Bob = 2*8=16 feet/min Bob will walk 16*60 = 960 feet in a minute Hence option A is correct Hit Kudos if you liked it 8-)

matthewsmith_89 · Answer

Joan 4
Al 8
Bob 16

Bob = 60 x 16 = 960 Answer A

JeffTargetTestPrep · Answer

Since Joan’s rate is 4 feet per second and her rate is half of Al’s rate, Al’s rate is 8 feet per second. Since Bob’s rate is twice as fast as Al’s, his rate is 16 feet per second.

Finally, since 1 minute = 60 seconds, Bob will walk 16 x 60 = 960 feet in a minute.

Answer: A

EgmatQuantExpert · Answer

Solution

• Joan walks at 4 feet per second.

• Joan walks half as fast as Al, which means,

o Joan  = \frac{(Al)}{2}

o  Al = 8  feet per second.

• Bob walks twice as fast as Al, which means,

o  Bob = 2*Al

o  Bob = 2* 8 = 16  feet per second.

• Distance traveled by Bob in a minute(60 seconds)  = Speed * Time = 16 * 60 = 960  feet.

• Thus, correct answer is   Option A  .

Thanks,
Saquib
Quant Expert
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ehsan090 · Answer

Option:A
Time taken:0:59
Joan=4 ft/sec
Al=2*Joan
Bob=2*Al
Therefore
Al=8 ft/sec
Bob=16 ft/sec
(Please read the question carefully may be you trapped by option E here)
for finding per minute spreed of Bob
Bob=16*60=960 ft/min

generis · Answer

When there is just one conversion, here, from seconds to minutes, I find it faster to convert before calculating.

Joan is half as fast as Al => Al is twice as fast as Joan, and Bob is twice as fast as Al.

Start with Joan, convert her rate, multiply by 2, then multiply by 2 again.

Joan =  \frac{4 ft}{1 sec}  x  \frac{60}{60}  =  \frac{240 ft}{60 secs}  =  \frac{240 ft}{1 min} , times 2 =>

Al =  \frac{480 ft}{1 min} , times 2 =>

Bob =  \frac{960 ft}{1 min}  Answer A.

Joan walks 4 feet per second, which is half as fast as Al walks. If B

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Joan walks 4 feet per second, which is half as fast as Al walks. If B

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