Imagine the letters(symbols) below to sit on scales.
Scale 1 and 2 are perfectly balanced.
Take D = diamonds H = Heart S = spades.
How many diamonds are needed to balance scale 3?
1. D H ........ S S S S
2. S S D D H ........ H H
3. H S S ........ ?
I get the same answer using both logic and algebra, yet it conflicts with the answer I have been given for this.