What are you asking for? Conversions? or a statistical analysis (i.e. mean, median, etc.)?
ANSWER
60 buttons.
EXPLANATION
Let the number of buttons in the container be x.
Then the number of buttons that are black are:

The number of buttons that are white

The difference between the white and the black buttons

Solve for x.



Hence there are 60 buttons in the container.
To find the unit rate you do distance ÷ time
16 miles ÷ 2 hours = 18
To find the time you do distance ÷ unit rate
20 miles ÷ 18 = 1.1
To find the distance you do time • unit rate
3 hours • 18 = 54
2) 1.1, 54, 1.8, 90, 27
3) 48, 3, 30, 2, 1
You are looking at right angles in the problem. Right angles are 90 degrees.
So set up the problem to solve for X using:
90=4x+12
90-12=4x
78=4x
39/2 or 19.5 = x