Eight. 4 children, their mother and father and one set of grandparents.

You will hang me. If they hang him, then the statement was true and they could only hang him for telling a lie. If they shoot him, then it makes the statement a lie and they were only to shoot him for telling the truth. An alternate solution is to say, “You will not shoot me,” leading to the same quandary for the killers.

Cut #1 – Down the center of the cake (vertically) leaving two equal halves.
Cut #2 – Across the center of the cake (horizontally) leaving four equal slices.
Cut #3 – Through the middle edge of the cake slicing all four of the pieces in equal halves, leaving eight equal slices (four equal tops and four equal bottoms).

7 cows, 21 pigs and 72 hens. The trick to this is finding the combination of cows and hens with the same cost and quantity since pigs are already equal. The magic combination is 7 cows and 72 hens, giving you 79 animals that cost $79 ($70 + $9). Then you just add 21 pigs to get to 100 animals.

The wise man said to switch camels.

Each son owns a camel, let’s call them Camel A and Camel B. If Camel A is slower, son A gets the fortune. If Camel B is slower, son B gets the fortune. Neither of the sons want to enter the city first because they won’t get the fortune.

When they switch camels, son A is now riding his brother’s camel (camel B) and son B is riding his brother’s camel (camel A). Now, they each want the camel they’re riding to get to the city first. If son A wins the race on camel B, that means his camel, camel A, was slower and he wins the fortune. The same is true for the other way around if the second son wins the race on camel A.