Question 1085322
<pre><b>
An integer is divisible by 4 if and only if the 
positive integer formed by the last two digits
is divisible by 4.

15_4,  the smallest digit that will make the number
       formed by the last two digits, _4, divisible 
       by 4 is 0, because 04 is the same as 4, which
       is divisible by 4.
       Answer: 15<u>0</u>4

21_4,  the smallest digit that will make the number
       formed by the last two digits, _4, divisible 
       by 4 is 0, because 04 is the same as 4, which
       is divisible by 4.
       Answer: 21<u>0</u>4

32_2,  the smallest digit that will make the number
       formed by the last two digits, _2, divisible 
       by 4 is 1, because 12 is the smallest 2-digit
       number which is divisible by 4.
       Answer: 32<u>1</u>2

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1_44,  The number formed by the last two digits, 44,
       is already divisible by 4, so 1_44 will be
       divisible by 4 regardless of what digit fills 
       the blank. So the smallest digit that can be 
       placed there is 0
       Answer: 1<u>0</u>44

163_,  the smallest digit that will make the number
       formed by the last two digits, 3_, divisible 
       by 4 is 2, because 32 is the smallest 2-digit
       number beginning with 3 that is divisible by 4.
       Answer: 16<u>3</u>2

33_2,  the smallest digit that will make the number
       formed by the last two digits, _2, divisible 
       by 4 is 1, because 12 is the smallest 2-digit
       number which is divisible by 4.
       Answer: 33<u>1</u>2

Edwin</pre></b>