Question 505943
If a number is half of some other number, you know
the larger number must be even, since you can't
take 1/2 of an odd number.
The 10's digit is even
The thousands digit is even also
The units and hundreds digits can't both be odd, 
since 2 odds make an even, and then the sum
couldn't be odd, so just 1 of the units and hundreds 
digits must be odd
So I could have
(a) EOEE or
(b) EEEO
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In terms of value,
b/2 , a , b , b/4
Notice that b gets divided by 2 twice. That means both
b and b/2 have to be even numbers.
Suppose 
b = 8
b/2 = 4
b/4 = 2
The sum is 14
That means 
a = 3
The number is 4382