Youseff lives x blocks from his office. It takes him 1 minute per bloc

Question

Youseff lives x blocks from his office. It takes him 1 minute per block to walk to work and 20 seconds per block to ride his bike to work. It is takes him exactly 10 minutes more to walk to work than to ride his bike to work, then x equals?

A. 4
B. 7
C. 10
D. 15
E. 20

A. 4 
B. 7 
C. 10 
D. 15 
E. 20

Henrikh lives x blocks from his office. It takes him 1 minute per block to walk to
work and 20 seconds per block to ride his bicycle to work. If it takes him exactly
10 minutes more to walk to work than to ride his bicycle, then x equals

○○ 4
○○ 7
○○ 10
○○ 15
○○ 20

A. 4
B. 7
C. 10
D. 15
E. 20

oa is d

I have solved it, by using backsolving but i tried one other method please tell me where am i wrong. I am not reasoning in minutes but in seconds and the result it is not the same
X/60-X/20 = 600

ENGRTOMBA2018 · Accepted Answer

Please follow posting guidelines, link is in my signatures.

As for your question, x/60 = blocks/time/block = block^2/time . This is not what you want. You are given x blocks and 60 seconds PER BLOCK. Thus you need to put it as 60*x to give you units of seconds as you are equating this to 600 (which is TIME in seconds.).

Thus the correct equation is : 60*x-20*x=600 ----> 40x=600--> x = 15.

EMPOWERgmatRichC · Answer

Hi siriusvj,

This question can be solved by TESTing THE ANSWERS.

We're given Youseff's rate to walk (1 minute/block) and bike (20 seconds/block = 1/3 minute/block) to work. We're also told that the DIFFERENCE in those two times is exactly 10 minutes. We're asked for the number of blocks between Youseff's home and work.

Since the DIFFERENCE is 10 minutes, and the walking rate is 1 minute/block, there MUST be MORE than 10 blocks (since 10 blocks = 10 minutes to walk and it takes a certain amount of time to bike, so the difference in time would be less than 10 minutes).

Let's TEST Answer D:

IF....15 blocks....
15(1 min/block) = 15 minutes to walk
15(1/3 min/block) = 5 minutes to bike
The difference IS 10 minutes, which is a MATCH for what we were told, so this MUST be the answer.

Final Answer:  D

GMAT assassins aren't born, they're made,
Rich

chetan2u · Answer

Hi
The best way would be...
Per km, he takes 40 secs extra if he walks
So he will take 10 mins or 10*60 secs in 10*60/40 =15 km

D

musunna · Answer

The key point to tackle the problem is to convert Time / second into a single unit.
For example, if we convert the figures in seconds, the equation could be 60x - 20x = 600.

Alternatively, if converting in minutes, we get- 
x - (1/3)x = 10
or, (2/3)x = 10
or, x = 15.

Push2018 · Answer

Solved this by converting to block per second measures. So it's 1 block per 60 seconds (Rate1) and 1 block per 20 seconds (Rate2). Solving for time it's x over 1/60 = 60x and x over 1/20=20x.

Time1 - Time2 or 60x - 20x=600; (the 600 derived from 10minutes converted to seconds)
40x=600/40;
x=15.

Answer is D.

JeffTargetTestPrep · Answer

We are given that Youseff lives x blocks from work. He can walk to work at a rate of 1 block per minute; thus, it takes him (1)(x) = x minutes to walk to work. We are also given that he can bike to work at a rate of 20 seconds per block or 20/60 = 1/3 minute per block; thus it takes him(1/3)x minutes to bike to work. Since it takes him 10 more minutes to walk to work than it does to ride, we can create the following equation to determine x:

x = (1/3)x + 10

3x = x + 30

2x = 30

x = 15

Answer: D

AyushCrackVerbal · Answer

Given:

Number of blocks between the office and home =  x

Time taken to walk 1 block = 1 minute

Time taken to walk to the office from home = 1 minute *  x = x  minutes

Time taken to cover 1 block by riding bicycle = 20 seconds =  \frac{20}{60}  minute =  \frac{1}{3}  minute

Time taken to ride a bicycle to the office from home =  \frac{1}{3}  *  x =   \frac{x}{3}  minutes

The difference in the time taken to walk to the office and ride a bicycle to office = ( x  -  \frac{x}{3} ) minutes = 10 minutes

\frac{2x}{3}  minutes = 10 minutes

x = 15

The correct answer is  D

ThatDudeKnows · Answer

We can just Plug In The Answers (PITA). I like trying B and D.

B:
7 blocks. 
1 minute per block to walk means 7 minutes to walk.
It can't take 10 minutes longer to walk if it doesn't even take 10 minutes to walk. B is out.

D: 15 blocks.
1 minute per block to walk means 15 minutes to walk.
20 seconds per block to bike means 5 minutes to bike.
That's a difference of 10 minutes. Yay!!

Answer choice D.

ThatDudeKnowsPITA

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Youseff lives x blocks from his office. It takes him 1 minute per bloc

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Youseff lives x blocks from his office. It takes him 1 minute per bloc

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