Answer:
140
Explanation:
Consider a square for just a second. It has 4 angles each of 90 degrees. The total number of degrees in a square is 4 * 90 = 360.
It should be at least an appeal to your intuition to say that a quadrilateral has a total of 360 degrees.
Therefore the ratio you have been given must have 4 angles that add to 360.
2x + 3x + 6x + 7x = 360
18x =360
x = 20
So the 4 angles are
2* 20 = 40
3*20 = 60
6*20 = 120
7*20 = 140
Total 360
The largest angle is 140