You have 8 Doughnuts all weigh the same amount except one which is heavier,you have a balance scale Whats the minium amount of weighings required for you to pick out the heaviest Doughnut every time
Weigh three doughnuts against three
If both batches weigh the same, discard and keep last two, and compare them in a second weigh
If one batch of three heavier, keep that, and weigh two of them against each other - if one heavier, that's it, else pick the third one