Challenge your students or kids with this mind-bending, critical thinking puzzles. Solving this kind of challenge requires a certain combination of creative thinking and logical reasoning.

## Challenge:

What is the next number?

3, 7, 23, 87, … ?

### The Absolute Best Book** to ****challenge your Smart Student!**

The correct answer is 343.

Find the pattern. First, try to find the relationship between the first and second numbers, 3 and 7.

7 is 3 plus 4, it’s also twice of 3 plus 1, or it’s three times of 3 minus 2, or 4 times of 3 minus 5.

Now, check the relationships with other numbers. For example 7 and 23.

23 is 7 plus 16. It’s also twice of 7 plus 9, or three times of seven plus 2, or four times of 7 minus 5. The last relationship is common for both 3 – 7 and 7 – 21.

Four times of 23 minus 5 is 87. Bingo!!

Therefore, the answer is: 4 × 87 – 5 = 343