OK geeks, you are too good, we need something more difficult. This one from 5th grade math book from Finland
Here we have a scale:
We have also 14 weights: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14 and 15 kilograms (pounds if you prefer). Notice that 11 kg (pound) weight is missing and not needed in this puzzle.
I have placed the one kg (pound) weight already, now you need to place the others so that the scale remains balanced. Notice that each colored bar doubles the counterweight a weight can balance as explained here:
(Those 2 and 4KG weights used here only as example; they need not to be placed in these places.)