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# A two digit number is randomly selected and multiplied by itself x

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Re: A two digit number is randomly selected and multiplied by itself x [#permalink]
hellosanthosh2k2 wrote:
Hi amanvermagmat

Question is Probability(unit digit of (two digit number)^x = 1) ?

Statement 1: is clearly sufficient
I have one question for statement 2.
I thought, x can be 0(as 0 also multiple of 4), in which case, whatever double digit number maybe, unit digit will be always one. and probability = 1

But the question clearly mentions as the number is mulitplied itself by 'x' times, so x can't be zero, it has to be some positive integer value, which is multiple of 4(as per statement2).

So statement 2 is also sufficient.

Is my understanding correct?

Hi

Yes, my reasoning is also same as yours. As it says in the question stem that number is multiplied by itself 'x' times, so saying a number multiplied by itself '0' times doesn't make sense. Hence we reject that possibility. x has to be 1 or more. And both statements mention that its a multiple of 4, so.. D answer
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Re: A two digit number is randomly selected and multiplied by itself x [#permalink]
amanvermagmat wrote:
hellosanthosh2k2 wrote:
Hi amanvermagmat

Question is Probability(unit digit of (two digit number)^x = 1) ?

Statement 1: is clearly sufficient
I have one question for statement 2.
I thought, x can be 0(as 0 also multiple of 4), in which case, whatever double digit number maybe, unit digit will be always one. and probability = 1

But the question clearly mentions as the number is mulitplied itself by 'x' times, so x can't be zero, it has to be some positive integer value, which is multiple of 4(as per statement2).

So statement 2 is also sufficient.

Is my understanding correct?

Hi

Yes, my reasoning is also same as yours. As it says in the question stem that number is multiplied by itself 'x' times, so saying a number multiplied by itself '0' times doesn't make sense. Hence we reject that possibility. x has to be 1 or more. And both statements mention that its a multiple of 4, so.. D answer

Thanks amanvermagmat
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Re: A two digit number is randomly selected and multiplied by itself x [#permalink]
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Re: A two digit number is randomly selected and multiplied by itself x [#permalink]
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