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he product of the units digit, the tens digit, and the
hundreds digit of the positive integer m is 96. What is
the units digit of m ?
(1) m is odd.
(2) The hundreds digit of m is 8.
plz explain
unit digit of m
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- pradeepkaushal9518
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IMO A.
The product of the digits is 96.
If we factorize 96 = 2 * 2 * 2 * 2 * 2 * 3
A says that units digit is odd that means there is only one possibility. Units digits has to be 3.
So,tens digit and hundred digits could be 8 (2 * 2 * 2 and 4 (2 * 2) OR 4 and 8.
B says hundred digit is 8.In that case units digit can be anything 4 or 3.
Please post the OA
The product of the digits is 96.
If we factorize 96 = 2 * 2 * 2 * 2 * 2 * 3
A says that units digit is odd that means there is only one possibility. Units digits has to be 3.
So,tens digit and hundred digits could be 8 (2 * 2 * 2 and 4 (2 * 2) OR 4 and 8.
B says hundred digit is 8.In that case units digit can be anything 4 or 3.
Please post the OA
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96 = 2^5 * 3
So the three digit number 'M' could be 843, 834, 348, 384, 682, 286, 862 ....
St1: m = odd
Only possibility for the odd digit is 3. All other factors of 96 are some even power of 2. hence if M = odd then its units digit must be 3.
Sufficient
ST2: Hundreds digit of m is 8
M could be 843 (units digit = 3) OR
M could be 834 (units digit = 4)
Hence Insufficient
Ans A
So the three digit number 'M' could be 843, 834, 348, 384, 682, 286, 862 ....
St1: m = odd
Only possibility for the odd digit is 3. All other factors of 96 are some even power of 2. hence if M = odd then its units digit must be 3.
Sufficient
ST2: Hundreds digit of m is 8
M could be 843 (units digit = 3) OR
M could be 834 (units digit = 4)
Hence Insufficient
Ans A