Machine A and machine B are each used to manufacture 660 sprockets. It takes machine A 10 hours longer to produce 660 sprockets than machine B. Machine B produces 10 percent more sprockets per hour than machine A. How many sprockets per hour does machine A produce?
A) 6
B) 6.6
C) 60
D) 100
E) 110
OA is A
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ssmiles08
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For Machine A, let r = rate, t = time.
r*t = 660
Machine B produces 10 hours less than A: t - 10
machine B's rate is 10% faster than A: 1.1r
(1.1r)(t - 10) = 660
set the equations equal to each other since they both equal 660
r*t = (1.1r)(t - 10)
rt = 1.1rt - 11r
1.1rt - rt - 11r = 0
.1t = 11
t = 110
r = 660/110 = 6
(A)
r*t = 660
Machine B produces 10 hours less than A: t - 10
machine B's rate is 10% faster than A: 1.1r
(1.1r)(t - 10) = 660
set the equations equal to each other since they both equal 660
r*t = (1.1r)(t - 10)
rt = 1.1rt - 11r
1.1rt - rt - 11r = 0
.1t = 11
t = 110
r = 660/110 = 6
(A)
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avanishjoshi
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Let the capacity of machine A = A sprockets/hr
Let the capacity of machine B = B sprockets/hr
Let B work for X hours to produce 660 sprockets
Then A(X + 10) = B(X)
But B produces 10% more sprockets per hour than A .Therefore B = 1.1A.
A(X + 10) = 1.1A(X) = > X+10 = 1.1X = > X = 100.
[spoiler]A (100 + 10) = 660 => A = 6 which is the ANSWER[/spoiler]
Let the capacity of machine B = B sprockets/hr
Let B work for X hours to produce 660 sprockets
Then A(X + 10) = B(X)
But B produces 10% more sprockets per hour than A .Therefore B = 1.1A.
A(X + 10) = 1.1A(X) = > X+10 = 1.1X = > X = 100.
[spoiler]A (100 + 10) = 660 => A = 6 which is the ANSWER[/spoiler]
660/ A -660/A+10= 10%(660/(A+10))Abdulla wrote:Machine A and machine B are each used to manufacture 660 sprockets. It takes machine A 10 hours longer to produce 660 sprockets than machine B. Machine B produces 10 percent more sprockets per hour than machine A. How many sprockets per hour does machine A produce?
A) 6
B) 6.6
C) 60
D) 100
E) 110
OA is A
10(A+10) -10A =A
10A+100 -10A=A
A=100
660/110=6
Choose A.
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Scott@TargetTestPrep
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We are given that machine A and machine B are each used to manufacture 660 sprockets; thus the work of each machine is 660. We also are given that it takes machine A 10 hours longer to produce 660 sprockets than it takes machine B, and that machine B produces 10% more sprockets per hour than machine A. If we let the rate of machine A = r, then the rate of machine B = 1.1r.Abdulla wrote:Machine A and machine B are each used to manufacture 660 sprockets. It takes machine A 10 hours longer to produce 660 sprockets than machine B. Machine B produces 10 percent more sprockets per hour than machine A. How many sprockets per hour does machine A produce?
A) 6
B) 6.6
C) 60
D) 100
E) 110
Since time = work/rate:
The time of machine A = 660/r and the time of machine B = 660/(1.1r) = 600/r
Since machine A takes 10 hours longer to produce 660 sprockets than does machine B, we can create the following equation and determine r:
660/r = 600/r + 10
60/r = 10
60 = 10r
6 = r
Thus, machine A produces 6 sprockets per hour.
Answer: A
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