The mean is 67530. But idk what background this question comes with
70 because 55+55 = 110 and a triangle is 180 so 180-110= 70 and X is opposite to the angle we worked out as the missing one
3.45 rounded to the nearest whole number would be 3 because 5 or more let it soar 4 or less let it rest
Let, Fiona's age = x
Darwin's age = 2x+6
Then, 2x+6 = 50
2x = 44
x = 22
So, your answer is 22
Hope this helps!