Machine A and Machine B are used to produce 660 rockets. It takes Machine A 10 hours longer to produce 660 rockets than machine B. Machines B produces 10 percent more rockets per hour than machine A. How many rocket per hour dose machine A produce?
A. 6
B. 6.6
C 60
D 100
E 110
Can anyone help?
Kaplan question 2
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Is the answer A?
Rate of rockets/hr=
R(A)=x rockets/1hr
R(B)=1.1xrockets/hr
thus time to make 660 rockets=
t(A)=660/x
t(B)=660/1.1x
but we know that it takes machine A 10 hours more than it takes machine B, so:
t+10=660/x
t=660/1.1x
substitute and solve for x.
Rate of rockets/hr=
R(A)=x rockets/1hr
R(B)=1.1xrockets/hr
thus time to make 660 rockets=
t(A)=660/x
t(B)=660/1.1x
but we know that it takes machine A 10 hours more than it takes machine B, so:
t+10=660/x
t=660/1.1x
substitute and solve for x.
- Neo2000
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Work from options. However note that whatever number you use, a 10% increment must also divide 660. Again, note that the speed cannot be big since time taken will decrease and if that happens, you will not be able to get a 10Hour difference
If we consider A i.e. 6 to produce 660 it will take 110hours
A 10% increment means 6.6 and it will take 100hours to produce 660
Thus this satisfies the Question
So Speed of A = 6
Old Fashioned Way
Let Speed of A = X
Speed of B = 1.1X
(660/X) - (666/1.1X) = 10
If we consider A i.e. 6 to produce 660 it will take 110hours
A 10% increment means 6.6 and it will take 100hours to produce 660
Thus this satisfies the Question
So Speed of A = 6
Old Fashioned Way
Let Speed of A = X
Speed of B = 1.1X
(660/X) - (666/1.1X) = 10