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Maurice entered a number into his calculator and erroneousl
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19 Jul 2019, 02:18
19 Jul 2019, 02:18
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46% (00:49) wrong based on 80 sessions
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Maurice entered a number into his calculator and erroneously divided the number by 0.03 instead of 0.0003, resulting in an incorrect result. Which of the following is a single operation that Maurice could perform on his calculator to correct the error?
Indicate all such operations.
A. Multiply the incorrect product by 100
B. Divide the incorrect product by 100
C. Multiply the incorrect product by 0.01
D. Divide the incorrect product by 0.01
Indicate all such operations.
A. Multiply the incorrect product by 100
B. Divide the incorrect product by 100
C. Multiply the incorrect product by 0.01
D. Divide the incorrect product by 0.01
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Re: Maurice entered a number into his calculator and erroneousl
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26 Jan 2020, 09:21
26 Jan 2020, 09:21
1
Carcass wrote:
Maurice entered a number into his calculator and erroneously divided the number by 0.03 instead of 0.0003, resulting in an incorrect result. Which of the following is a single operation that Maurice could perform on his calculator to correct the error?
Indicate all such operations.
A. Multiply the incorrect product by 100
B. Divide the incorrect product by 100
C. Multiply the incorrect product by 0.01
D. Divide the incorrect product by 0.01
Indicate all such operations.
A. Multiply the incorrect product by 100
B. Divide the incorrect product by 100
C. Multiply the incorrect product by 0.01
D. Divide the incorrect product by 0.01
One approach is to choose an arbitrary value for the number that Maurice FIRST entered into his calculator BEFORE he accidentally divided by 0.03 (instead of 0.0003)
Let's say that 0.03 is that FIRST value.
So, Maurice INTENDED to divide 0.03 by 0.0003. IF he had performed the correct operation, he would have calculated 0.03/0.0003 = 100.
INSTEAD, Maurice accidentally divided 0.03 by 0.03. So, Maurice's incorrect calculation = 0.03/0.03 = 1
So, what must we do to the incorrect answer (1) in order to get the correct answer (100)?
Let's check the answer choices...
A. Multiply the incorrect product by 100. If we multiply 1 by 100, we get 100. PERFECT!
B. Divide the incorrect product by 100. If we divide 1 by 100, we get 0.01. NO GOOD
C. Multiply the incorrect product by 0.01. If we multiply 1 by 0.01, we get 0.01. NO GOOD
D. Divide the incorrect product by 0.01. If we divide 1 by 0.01, we get 100. PERFECT!
Answer: A & D
Cheers,
Brent
Re: Maurice entered a number into his calculator and erroneousl
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09 Aug 2023, 21:59
09 Aug 2023, 21:59
1
In case someone wants to solve algebraically (p.s. I do not recommend since it might complicate things 
)
let the value that can give Maurice the correct result be "x" and the original number be "a" .
thus we can either multiply or divide by x to get the correct result .
Equation1 - Multiply
a*x/0.03 = a/0.0003 --> ax/3*10^-2 = a/3*10^-4
now multiply both sides by 3*10^-4 we get --> ax*10^-2=a
dividing both sides by a we get --> x*10^-2=1 --> x/100 =1 --> x=100 i.e. Multiply by 100
Equation 2 - Divide
a/x*0.03 = a/0.0003 --> a/x*3*10^-2 = a/3*10^-4
now multiply both sides by 3*10^-4 we get -->10^-2/ax = a
dividing both sides by a we get --> 10^-2/x=1 --> x=10^-2 or 0.01 i.e. Divide by 0.01
)let the value that can give Maurice the correct result be "x" and the original number be "a" .
thus we can either multiply or divide by x to get the correct result .
Equation1 - Multiply
a*x/0.03 = a/0.0003 --> ax/3*10^-2 = a/3*10^-4
now multiply both sides by 3*10^-4 we get --> ax*10^-2=a
dividing both sides by a we get --> x*10^-2=1 --> x/100 =1 --> x=100 i.e. Multiply by 100
Equation 2 - Divide
a/x*0.03 = a/0.0003 --> a/x*3*10^-2 = a/3*10^-4
now multiply both sides by 3*10^-4 we get -->10^-2/ax = a
dividing both sides by a we get --> 10^-2/x=1 --> x=10^-2 or 0.01 i.e. Divide by 0.01
