SOLUTION: Hi. I need some help solving this problem please.
Jack can mow the baseball grounds in 6 hours; Mike can mow the same grounds in 5 hours and Chris can mow the grounds in 4 hours
Question 845497: Hi. I need some help solving this problem please.
Jack can mow the baseball grounds in 6 hours; Mike can mow the same grounds in 5 hours and Chris can mow the grounds in 4 hours. How long will it take to mow the grounds if all 3 work together? (Leave the answer in improper fraction form)
This is what I came up with but i'm not too sure:
1/6 + 1/5 + 1/4 = 1/t(time)
10t + 12t + 15t= 37t
37t/37 = 60/37 t=60/37
Thanks in advance.
Hi,
1/6 + 1/5 + 1/4 = 1/t Yes. Good Work.
|Multiplying thru by so as all denominators = 1
10t + 12t + 15t = 60
37t = 60
t = 60/37 hrs
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website! Jack can mow the baseball grounds in 6 hours
Jack rate = 1/6 job/hr
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Mike can mow the same grounds in 5 hours
Mike rate = 1/5 job/hr
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and Chris can mow the grounds in 4 hours.
Chris rate = 1/4 job/hr
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Together rate = 1/x job/hr
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Equation:
rate + rate + rate = together rate
[ 1/6 + 1/5 + 1/4] = 1/x
x[(5*4 + 6*4+ 6*5)/(6*5*4)] = 1
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x(74/120) = 1
x = 120/74 = 1.62 hours = 1 hr 37 min 18 sec
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Note: Your answer is correct.
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