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Push Mower
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It takes 5 hours to complete the job
1 hour = 1/5 of the job
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Riding Lawn Mower
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It takes 3 hours to complete the job
1 hour = 1/3 of the job
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Push Mower + Riding Lawn Mower
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1 hour = 1/5 + 1/3
1 hour = 3/15 + 5/15
1 hour = 8/15 of the job.
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Calculate time needed to complete
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8/15 of the job takes 1 hour
8/15 of the job = 1 hour
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Divide by 8/15 on both side
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8/15 ÷ 8/15 of the job = 1 ÷ 8/15 hour
Whole of the job = 1 x 15/8 hours
Whole of the job = 15/8 hours
Whole of the job = 1 7/8 hours
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Answer: 1 7/8 hours
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If you would like to find the matching equation, you can do this using the following steps:
ax^2 + bx + c = 0
a = -2
b = 1
c = 3
-2x^2 + x + 3 = 0
The correct result would be a. 0 = <span>-2x^2 + x + 3.</span>
The answer is: 
The explanation is shown below:
1. Cynthia rounds the number, which is identified as
, to one decimal place and the result is 6.3.
2. Based on this, we know that
could have been between 6.25 and 6.35. Therefore, the error interval for
is given by:

Where
indicates that the value 6.25 is included and
indicates that the value 6.35 is not included (Because if
had been exactly 6.35, Cynthia would round up to 6.4).
Then your amount was reduced to $15 less
Helena can make 2 loaves of bread and 4 batches of muffins.