existA) We are looking at the number product that has got maximum values.
We simply get a number that can give us the highest multiples from the listed numbers, (8,7,6,3)
These multiples have to be the highest obtainable.
That way, their leading numbers have to be the highest available, i.e. 8 and 7
We are left with 763 x 8 OR 863 x 7
763 x 8 = 6104 > 863 x 7 = 6041
Therefore, 763 x 8 = 6104 is the greatest product
B) These multiples have to be the lowest obtainable.
That way, the leading numbers of the multiples will be 3 and 6.
Two possibilities exists for these:
378 x 6 = 2268 and 678 x 3 = 2034
678 x 3 = 2034 < 378 x 6 = 2268
This leaves 678 x 3 = 2034 as the least obtainable multiple