Question on Math destroyer #13

[pandalove89]

For the 2010 Math Destroyer the question asks:


Two work crews, Crew A and B start digging a 300-foot tunnel through a mountain, but working toward each other from opposite sides. If Crew A digs at a rate of 12 ft per day and Crew B digs 18 feet per day how many feet will crew A have dug when the two crews meet.

I solved it like this:

Since Crew A works at a rate of 12 ft/ 1 day and Crew B works 18 ft / 1 day then the two work at a rate of 30 ft / 1 day. Therefore, it takes them 10 days to complete (because 10 days x 30 ft / 1 day = 300 ft). So that means 10 x 12 ft per day = 120 feet for Crew A.

However, the answer in the solution is 180 ft which would be Crew B....

What gives????

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[PooyaH]

Are you sure? Mine's the 2011 version and it says it's A: 120 feet! And 120 feet is correct.

 

[radmazindds]

I think you just have to find the least common multiple of 18 and 10.

EDIT: I LIIIIIIED! MISREAD THE QUESTION!!!!!!!

For the 2010 Math Destroyer the question asks:


Two work crews, Crew A and B start digging a 300-foot tunnel through a mountain, but working toward each other from opposite sides. If Crew A digs at a rate of 12 ft per day and Crew B digs 18 feet per day how many feet will crew A have dug when the two crews meet.

I solved it like this:

Since Crew A works at a rate of 12 ft/ 1 day and Crew B works 18 ft / 1 day then the two work at a rate of 30 ft / 1 day. Therefore, it takes them 10 days to complete (because 10 days x 30 ft / 1 day = 300 ft). So that means 10 x 12 ft per day = 120 feet for Crew A.

However, the answer in the solution is 180 ft which would be Crew B....

What gives????

 

[AlbinoPolarBear]

Are you sure? Mine's the 2011 version and it says it's A: 120 feet! And 120 feet is correct.

Should be 120 for A and 180 for B.

 

[NOORALLAH]

so i think ur pretty right, cuz i did the same thing you did and came up with the same answer..

 

[Dental2000]

ans should be 120 feet....which test no. is the question in in the Math destroyer?

 

[LetsGo2DSchool]

I have the 2010 version and it's a typo in the solution.

 

[toothhornet88]

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