Not a 5 dollar just means a 10 dollar
probblity=desired outcomes/total possible outcomes
desired=number of 10 dollar notes or 30
total possible=10+30 or 40
the probablity is 30/40 or 3/4 or 75% that you do not select a 5 dollar note
Multiply the cost by 1.2 (120%) to add 20% tip, and then multiply by 0.85 (85%) to take off 15%
78.96 x 1.2 x 0.85 = 80.54

Substract '-3.4x' at LHS nad the RHS of the above expression.

Add '4' on both LHS and RHs of the above expression.
5.7 mile ride on the community bike ride
3, 12, 15, 25, 30, 40The range is the difference between the greatest and smallest values:
range = 40 - 3 = 37
Thee average is the sum of elements divided by the number of elements:
average = (<span>3 + 12 + 15 + 25 + 30 + 40</span>)/6
average = 125/6 = 20.83