Below is a pyramid of numbers where the number on each brick is the sum of two bricks below it. The numbers given will help you fill in the entire pyramid.
The answer is 43.
You need to fill number in the bricks in the image below such that the top brick is sum of two brick below it.
Find out the missing number in the picture attached:
Find the missing number.
12 3 1
40 5 3
7 1 ?