The mean (average) can be found by adding up all ur numbers, then dividing by how many numbers there are.
(0.7+1.1+0.8+1.6+1.6+2.2+1.1) / 7 = 9.1 / 7 = 1.3 <==
3 yrs ago:
Alice - x
Jane - 3x
Fast forward 2 years... 1 year ago:
Sum of their ages = 62
Equation to solve: x + 3x = 62
4x = 62
----- -----
4 4
x = 15.5
From this, we can deterime that Alice is 15 1/2 years old.
Then, plug in 15.5 for x in 3x to find Jane's age.
15.5 × 3 = 46.5
From this, we can determine that Jane is 46 1/2 years old.
I hope this helps you to understand this problem better.