<PRE><B>Question 1051626</B>
the electrician can wire 1/12 of a house per hour.
apprentice can do 1/16 of a house per hour.
(4/12)+(x/16)=1; that means that the two together after x hours will do the whole house.
Multiply by 48 to clear fractions
16+3x=48
3x=32
x=32/3 or 10 2/3 hours.
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check this by realizing the first electrician has done 1/3 the house.
The second one has to do 2/3 of the house and we know it takes 16 hours to do the whole house.  16*(2/3)=32/3 hours.
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