Answer: 2.5 hours
This is equivalent to equivalent to 2 hours, 30 minutes.
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Work Shown:
1/3 of the house = 50 minutes
3*(1/3 of the house) = 3*(50 minutes)
3/3 of the house = 150 minutes
1 house = 150 minutes
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Sam will need 150 minutes to clean the whole house
Divide this over 60 to convert to hours
150 minutes = (150/60) hours
150 minutes = 2.5 hours which is the final answer
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Or you could say the following
150 minutes = 120 min + 30 min
150 minutes = (120/60) hr + 30 min
150 minutes = 2 hr + 30 min
This shows that 2.5 hours is equivalent to 2 hours, 30 minutes.