The blank squares in the figure must be filled with numbers in such a way that each number, starting from the second row, is equal to the sum of the two adjacent numbers in the immediately preceding row. For example, the number in the first cell of the second row is 11, because $11=5+6$. What number will appear in the square marked with $\times$?

(a) 4

(b) 6

(c) 9

(d) 15

(e) 10

![](https://cdn.mathpix.com/cropped/2024_05_01_280b19a87fa67143351eg-006.jpg?height=323&width=554&top_left_y=1606&top_left_x=700)
The correct option is (e).

Filling the board according to the rules of the problem, it follows that $60=(x+17)+(2x+13)=3x+30$, from which $x=10$.

![](https://cdn.mathpix.com/cropped/2024_05_01_280b19a87fa67143351eg-042.jpg?height=449&width=762&top_left_y=478&top_left_x=727)