Simple question:
* If x is an integer divisible by 15 but not divisible by 20, then x CANNOT be divisible by which of the following?
-------------6
-------------10
-------------12
-------------30
-------------150
The way I approached it is -- To be divisible by 15, but not by 20 would mean it needs to be divisible by 3, 5 but not 2, 4?
I know the answer but I am hoping someone explains to me in a simple way why/how?
Thanks,
uhsa
Simple MATH question but having brain fart!
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- kvcpk
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x is divisible by 15 but not 20.
x is divisible by 5 and 3
x is not divisible by 5 and 4
Hence x should be divisible by 3 but not by 4
Hence x cannot be divisible by 3*4 = 12
Hope this helps!!
x is divisible by 5 and 3
x is not divisible by 5 and 4
Hence x should be divisible by 3 but not by 4
Hence x cannot be divisible by 3*4 = 12
Hope this helps!!
- kvcpk
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I actually took an example of 30. 30 is divisible by 15 but not by 20.uhsa wrote:kvcpk,
That would mean that out of the answers given, 10, 30 and 150 are not divisible by 12?
Now 30 is div by 6,10,30 - ABD out
If I take x = 150, I see that x is also divisible by 150.
Hence picked C
- Gurpinder
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just take 150 because its divisble by 15 and not by 20.
you can also take a small number like 30, but you will have a problem with it when you go to 150. so pick the biggestest one from the options.
so 150/6 = 25
150/10 = 15
150/12 = a fraction
150/30 = 5
150/150=1.
so theres your answer.
you can also take a small number like 30, but you will have a problem with it when you go to 150. so pick the biggestest one from the options.
so 150/6 = 25
150/10 = 15
150/12 = a fraction
150/30 = 5
150/150=1.
so theres your answer.