SOLUTION: A farmer can plow a field in 9 hours, and his son can do it in 18 hours. After the farmer had plowed it for 3 hours, the boy joined him and together they completed the plowing of
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-> SOLUTION: A farmer can plow a field in 9 hours, and his son can do it in 18 hours. After the farmer had plowed it for 3 hours, the boy joined him and together they completed the plowing of
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Question 846551: A farmer can plow a field in 9 hours, and his son can do it in 18 hours. After the farmer had plowed it for 3 hours, the boy joined him and together they completed the plowing of the field. How long did it take them? Answer by ewatrrr(24785) (Show Source):
Hi,
farmer had plowed it for 3 hours, the boy joined him ... 2⁄3 of work left
Will take each 2⁄3 of the time and |Multiplying thru by 12x so as all denominators = 1
2x + x = 12
3x = 12
x = 4hrs
