I have in mind 4 positive numbers, which I would like you to find.
Out of the set of 6 pairwise products of those numbers I am going to omit one.
The remaining five are: 8,10,12,24,30.
The 8 must be 1*8 or 2 * 4.
If it were 1*8, there'd be a 3 for the 24, the only other multiple of 8 there. But you also need a 2 and a 5 for the 10.
So there are 2, 4 and 5. To get the 30 you also need a 6.
The numbers are 2, 4, 5 and 6. The missing product is 5 * 4 = 20.
Edited on February 25, 2016, 7:55 am

Posted by Charlie
on 20160224 12:18:06 