10 Tricky Riddles That Will Make Your Brain Strain

Solving puzzles helps improve our cognitive processes, strengthens the connections between brain cells, and improves memory. And they’re also a lot of fun! So, by solving riddles, you’re basically killing 2 birds with one stone.

We at Bright Side like to solve some interesting and difficult puzzles. This time we found 10 riddles for you, where you need to use your logic and attention to detail. Take your time and enjoy!

3. The bat and ball riddle

A bat and a ball together cost \$1.10. The bat costs \$1 more than the ball. How much does the ball cost?

4. The widget-making machine riddle

If it takes 5 machines 5 minutes to make 5 widgets, how long would it take 100 machines to make 100 widgets?

5. The size-double lily pad patch problem

There is a patch of lily pads in a lake. Every day, the patch doubles in size. If it takes 48 days for the patch to cover the entire lake, how long would it take for the patch to cover half the lake?

6. Connect the dots logic puzzle

You have a grid of 9 dots. The grid is 3 rows by 3 columns, as in the picture. Using 4 straight lines and without lifting your pencil, draw through each dot once.

7. The 7 candles logic puzzle

There is a big round cake with 7 candles along the cake’s edges. You need to blow out all of the 7 candles, which are placed in a circle. The rule is: once you blow out one candle, the candles near it will also be extinguished. If you blow on an extinguished candle, it will reignite. So if you blow on a candle, it will go from lit to unlit, and vice versa (as well as the candles on either side). How can you extinguish all of the candles with the fewest blows?

Hint: Blowing on the same candle twice is the same as not blowing on it at all. Blowing on the same candle 3 times is the same as blowing on it once.

8. One light and 3 switches

There is a lightbulb inside a closet which is closed. You can’t see if the light is on or off through the door. Though you know that the light is off from the start. There are 3 light switches outside the closet and one of the switches controls the lightbulb. You can flip the switches in whatever way you want, but once you open the door, you are not allowed to touch the switches anymore.

Which switch controls the light?

9. Apples and oranges brain teaser

You have 3 boxes. One box has oranges, one has apples and one has oranges and apples together. The first box is labeled as “apples,” the second one as “oranges,” and the third one as “apples and oranges.” Sadly, all 3 boxes are labeled wrong, so you have to fix them. You can’t peek inside any of the boxes, but you can ask for a sample from any box. What is the minimum number of samples that you need to ask in order to label all the boxes correctly?

10. The hourglass logic puzzle

There are 2 hourglasses in front of you. One hourglass measures 7 minutes, the other one measures 4 minutes. How do you time 9 minutes by using only these 2 hourglasses?