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a,b,c and d are all positive integers.....
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Updated on: 07 Oct 2022, 05:24
Updated on: 07 Oct 2022, 05:24
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Question Stats:
47% (01:33) correct
52% (01:39) wrong based on 34 sessions
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If a, b, c, and d are all positive integers. \(\frac{ab}{c+d}=3.7\), which of the following statements must be true ?
Indicate all such statement
A. ab is divisible by 5
B. c+d is divisible by 5
C. If c is even, then d must be even
Indicate all such statement
A. ab is divisible by 5
B. c+d is divisible by 5
C. If c is even, then d must be even
Originally posted by NeophyteNitol on 07 Jun 2017, 06:38.
Last edited by Carcass on 07 Oct 2022, 05:24, edited 2 times in total.
Last edited by Carcass on 07 Oct 2022, 05:24, edited 2 times in total.
UPDATED
Re: a,b,c and d are all positive integers.....
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07 Jun 2017, 11:01
07 Jun 2017, 11:01
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Please type the question and specify the official answers.
Please follow the community guidelines for posting. It helps other students as well!
Now a, b, c and d are all positive integers and given that
\(ab = 3.7 \times (c+d)\). Now \(ab\) also must be an integer as as product of two integers is an integer.
\(3.7=\frac{37}{10}\). This is lowest reducable form as 37 and 10 have no common factors.
So \(c+d\) must have a factor of 10. So \(c+d\) is an even number with a factor of 10.
Hence option B and C are correct!
Now option A is not correct because if \(c+d\) is 10 then \(ab=37\), which is not divisible by 5.
Please follow the community guidelines for posting. It helps other students as well!
Now a, b, c and d are all positive integers and given that
\(ab = 3.7 \times (c+d)\). Now \(ab\) also must be an integer as as product of two integers is an integer.
\(3.7=\frac{37}{10}\). This is lowest reducable form as 37 and 10 have no common factors.
So \(c+d\) must have a factor of 10. So \(c+d\) is an even number with a factor of 10.
Hence option B and C are correct!
Now option A is not correct because if \(c+d\) is 10 then \(ab=37\), which is not divisible by 5.
Re: a,b,c and d are all positive integers.....
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24 Jun 2022, 17:06
24 Jun 2022, 17:06
sandy, why do we need to look for the lowest reducible form of 3.7?
