Algebra-2

In Pascal's Triangle, each number (except for the 1s on the edges of each row) is the sum of the two numbers directly above it in the previous row.

 

Let's look at the row where the missing number is located. It's the third row.

The second row has two numbers: 1 and 1. To find the missing number in the third row which is between these two 1s, we add the two numbers from the second row that are directly above it.

 

Since 1 + 1 = 2, the missing number (the one replacing the "?") in Pascal's Triangle is 2.

The completed Pascal's Triangle would look like this:

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