Answer:
36
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Explanation:
The object of the question to find the number inside the third triangle.
This object can be achieved with the help of the first two triangles by finding the relation between the four numbers of each triangle.
For the first triangle the numbers are: 51 , 17 , 3 , 102
By try and error, we can find that ⇒ ( 51 -17 ) * 3 =102
We can check this relation for the second triangle
The numbers of the second triangle are: 71 , 19 , 7 , 364
⇒⇒⇒ ( 71 - 19 ) * 7 = 364
So, Applying the same rule for the third triangle
The numbers of the third triangle are: 22 , 18 , 9 , ???
∴ ( 22 - 18 ) * 9 = 36
So, the missing number is 36