What numbers should replace the question marks in the sequence?
Correct answer: 45, 9
Explanation:
The sequence is 30, 31, 27, 36, 20, ?, ?.
Look at how the numbers change:
30 + 1 = 31
31 - 4 = 27
27 + 9 = 36
36 - 16 = 20
The pattern is alternating adding and subtracting square numbers:
+1, -4, +9, -16
These are:
1 = 1²
4 = 2²
9 = 3²
16 = 4²
So the next steps are:
+25 and -36, because 25 = 5² and 36 = 6².
Continue the sequence:
20 + 25 = 45
45 - 36 = 9
Therefore, the missing numbers are 45 and 9.
Finall answer to this puzzle: 45, 9
