What number fits the sequence, and why?
What is the actual sequence?
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Answer:
The number is 15.
Step-by-step explanation:
If you look closely, the sum of any two adjacent boxes in the bottom row gives the number in the top row. For example, the sum of the first two boxes 27 and 18 gives the number 45.
27+18 = 45
Similarly,
21+x = 36 (Third and fourth boxes in bottom row)
Solving, we get x=15.
We can confirm this by checking with the last two boxes.
x+13 = 28
x=15
So, the answer is 15.
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