SOLUTION: Winston works faster. Winston can mow his dad’s lawn in 1 hour less than it takes his brother Willie. If they take 2 hours to mow it when working together, then how long would it t
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-> SOLUTION: Winston works faster. Winston can mow his dad’s lawn in 1 hour less than it takes his brother Willie. If they take 2 hours to mow it when working together, then how long would it t
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Question 42722: Winston works faster. Winston can mow his dad’s lawn in 1 hour less than it takes his brother Willie. If they take 2 hours to mow it when working together, then how long would it take Winston working alone? Found 2 solutions by fractalier, Socom491:Answer by fractalier(6550) (Show Source):
You can put this solution on YOUR website! The working equation for this kind of problem is
t/A + t/B = 1
where t is the time worked together and A and B are individual times...
Here t = 2...if we let A be Winston's time, then Willie's time is A + 1...we have
2/A + 2/(A+1) = 1
Now multiply through by the LCD and solve...we get
2(A + 1) + 2A = A(A + 1)
2A + 2 + 2A = A^2 + A
A^2 - 3A - 2 = 0
This can't be factored so use the quadratic...
A = (3 ± sqrt(9 + 8)) / 2
A = (3 ± sqrt(17)) / 2
Since time can't be negative, Winston's time must be
(3 + sqrt(17)) / 2 or about 3.7 hours...
You can put this solution on YOUR website! Let x= Amount it takes Willie to mow lawn.
Let x-1= Amount of time it takes Winston to mow lawn.
Now it says that if they both do the lawn, it takes 2 hours, so we add both of the times and have them equal 2 hours.
But remember, x equals the amount it takes willie to mow the lawn, so to get winstons time, we subtract one hour. We are then left with .5, or a half hour.It takes winston a half hour to mow his dad's lawn if he's working by himself.
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