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, … ?
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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
