If k is a positive three-digit integer, what is the hundreds digit of k?
1) The hundreds digit of K +150 is 4
2) The tens digit of K + 25 is 7
OA is E
Please explain
three digit positive k
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IMO Ctj123 wrote:If k is a positive three-digit integer, what is the hundreds digit of k?
1) The hundreds digit of K +150 is 4
2) The tens digit of K + 25 is 7
OA is E
Please explain
From 1.
If K = 704, K+ 150 = 854 - Hundred Digit = 4, Also hundred Digit of K = 4
If K= 990, K + 150 = 1140 - Hundred Digit = 4 , But hundred digit of K =0
From 2.
Clearly, we say of hundred digit, just from tens' digit.
Combining I and II, ten's digit should always be 5. Hundred should be 4.And Unit's digit can vary.
K=154
K+25=179
K+150=304
I cannot think of any number, which satisfies I and II, and its hundredth digit is not 4.
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I think it is E.
1)
XXX + 150 = 4XX
The numbers that satisfy this condition range from:
250 to 349.
So therefore the hundreds digit can be 2 or 3 and Insufficient.
2)
XXX + 25 = X7X
The numbers that satisfy this condition range from:
X45 to X54.
So therefore the hundreds digit can be 1 to 9 and Insufficient.
Combined:
Using the info above the range of numbers are:
250 to 254 or 345 to 349.
So therefore the hundreds digit can be 2 or 3.
Therefore E.
1)
XXX + 150 = 4XX
The numbers that satisfy this condition range from:
250 to 349.
So therefore the hundreds digit can be 2 or 3 and Insufficient.
2)
XXX + 25 = X7X
The numbers that satisfy this condition range from:
X45 to X54.
So therefore the hundreds digit can be 1 to 9 and Insufficient.
Combined:
Using the info above the range of numbers are:
250 to 254 or 345 to 349.
So therefore the hundreds digit can be 2 or 3.
Therefore E.