X=2.543*10^K, where k is an integer, what is the thousandth digit of x?
1). The hundredth digit of x is 0
2). Hundredth digit minus thousandth digit is 3
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user123321
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1) hundredth digit of x is 0.sud21 wrote:X=2.543*10^K, where k is an integer, what is the thousandth digit of x?
1). The hundredth digit of x is 0
2). Hundredth digit minus thousandth digit is 3
we dont know anything about k whether it is +ve or -ve. so insuff.
2) this can happen only when k = 1 then 3-0 = 3.
hence suff.
[spoiler]is it B?[/spoiler]
user123321
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chufus
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The answer should be B but i think you are subtracting the wrong nos.. It should be 5- 2 = 3user123321 wrote:1) hundredth digit of x is 0.sud21 wrote:X=2.543*10^K, where k is an integer, what is the thousandth digit of x?
1). The hundredth digit of x is 0
2). Hundredth digit minus thousandth digit is 3
we dont know anything about k whether it is +ve or -ve. so insuff.
2) this can happen only when k = 1 then 3-0 = 3.
hence suff.
[spoiler]is it B?[/spoiler]
user123321
Otherwise it would have to be 0 -3 = -3 not 3.
the number will be 2543
Its the hundredth digit minus the thousands digit. So K will have to be 3 for 2.543 to become 2543 and only then will the difference be 3
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user123321
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Hichufus wrote:The answer should be B but i think you are subtracting the wrong nos.. It should be 5- 2 = 3user123321 wrote:1) hundredth digit of x is 0.sud21 wrote:X=2.543*10^K, where k is an integer, what is the thousandth digit of x?
1). The hundredth digit of x is 0
2). Hundredth digit minus thousandth digit is 3
we dont know anything about k whether it is +ve or -ve. so insuff.
2) this can happen only when k = 1 then 3-0 = 3.
hence suff.
[spoiler]is it B?[/spoiler]
user123321
Otherwise it would have to be 0 -3 = -3 not 3.
the number will be 2543
Its the hundredth digit minus the thousands digit. So K will have to be 3 for 2.543 to become 2543 and only then will the difference be 3
2.543 * 10 = 25.430
in this hundredths digit is 3 and thousandths digit is 0
so hundredths - thousandths = 3 - 0 = 3
Please let me know if my logic is wrong.
Thanks,
user123321
Just started my preparation
Want to do it right the first time.
Want to do it right the first time.
