I just kind of sat here playing with numbers i dont really know a shortcut but the answer is 10 chickens and 15 rabbits
10*2= 20 each chicken has two legs so thats 10 heads 20 legs
15*4=60 each rabbit has four legs so thats 15 heads 60 legs
15+10=25 heads
20+60=60 legs
Answer: total profit = $418
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Work Shown:
June
Income = (4 lawns)*($27 per lawn) = $108
Expenses = ($32 for gas)+($12 for trim line) = $44
Profit = income - expenses = 108-44 = $64
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July
Income = (12 lawns)*($20 per lawn) = $240
Expenses = ($89 for gas)+($29 for blade sharpening) = $118
Profit = income - expenses = 240 - 89 = $151
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August
Income = (16 lawns)*($20 per lawn) = $320
Expenses = ($101 for gas)+($16 for oil) = $117
Profit = income - expenses = 320-117 = $203
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Total profit = (june profit)+(july profit)+(august profit)
Total profit = (64) + (151) + (203)
Total profit = $418
If the final result was negative, then we would call this a loss. However, we have a positive value, so we go with a profit.
($3.91)(0.09) = $0.3519
$3.91 + 0.3519 = $4.2619 per gallon
if you're looking for the total expense next year:
($4.2619)(370 gallons) = $1,576.903