unit digit of m

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unit digit of m

by pradeepkaushal9518 » Wed May 22, 2013 5:24 pm
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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
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by aaggar7 » Wed May 22, 2013 6:15 pm
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

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by apoorva.rattan » Wed May 22, 2013 6:22 pm
Wouldn't the above explanation mean that the answer is C.

IMO C - Both

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by aaggar7 » Wed May 22, 2013 6:37 pm
Hi Apoorva,

The question stem is -What is the unit's digit?

With statement A alone we were able to figure out that unit digit has to be 3.

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by pradeepkaushal9518 » Thu May 23, 2013 6:43 pm

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by ygdrasil24 » Fri May 24, 2013 2:02 am
Whats the answer ? IMO it shud be A

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by srcc25anu » Fri May 24, 2013 5:05 am
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