Math Riddles

These Math Riddles are based on math concepts and can be solved with a bit of math and logic. These fun riddles can surely give you a tough time.

Half Full Recycling Bin

There is a bottle recycling bin, with one lonely bottle inside. Every hour, on the hour, people come and put bottles into the skip. The first hour, at noon, one person came and put a bottle in. One hour later, two people placed a bottle each into the skip. An hour later four people placed a bottle each into the skip.

This doubling of people continued until 11pm, when the bin was finally full. When was the bin exactly half full?

Riddle Answer

Bus Company Expansion

A bus company has recently expanded and no longer has enough room for all of its buses. Twelve of their buses have to be stored outside.

If they decide to increase their garage space by 40%, this will give them enough room for all of their current buses, plus enough room to store another twelve in the future.

How many buses does the company currently own?

Riddle Answer

Largest Amount of Area with Least Amount of Fence

A farmer challenges an engineer, a physicist, and a mathematician to fence off the largest amount of area using the least amount of fence.

The engineer made his fence in a circle and said it was the most efficient.

The physicist made a long line and said that the length was infinite. Then he said that fencing half of the Earth was the best.

The mathematician laughed at the others and with his design, beat the others. What did he do?

Riddle Answer