If the mean is 20.8, one standard deviation each way is adding and subtracting 3.1, so 17.7 and 23.9 (68% of values)
Two standard deviations adding and subtracting 3.1*2 = 6.2, or 14.6 and 27.
Three standard deviations is 11.5 and 30.1
So we have
11.5 - 14.6 - 17.7 - 20.8 - 23.9 - 27 - 30.1
Going left to 11.5 is 3 standard deviations out, so 99.7/2 = 49.85%
Going right to 27 is 2 standard deviations out, so 95/2 = 47.5%
Add those two % to get 97.32%
This is hard to do without a picture so I hope that helps!
2 $1 bills would equal $2 because they are $1 bills 1+1=2. Three quarters would equal .75 cents because a quarter equals .25 cents
Area of the entire rectangle 
Solution:
Area of the blue box = length × width

Area of the blue box 
Area of the pink box = length × width

Area of the pink box 
Area of the green box = length × width

Area of the green box 
Area of the orange box = length × width

Area of the orange box = 24
Total area of the rectangle 

Area of the entire rectangle