Question

An uber charges a flat rate of $6 plus $1.25 per mile. Kayla can spend no more than $27.50. If she wants to tip her driver $4, what is the greatest number of miles she can uber? Define the Variable for situation #1 and write an equation or inequality that represents this situation using the variable

Answer 1

The cost of the uber is a $6 flat rate plus $1.25 per mile.

Then if you take an uber for x miles, the cost will be:

c(x) = $1.25*x + $6

Now, in this case Kayla also wants to add a tip of $4, then the total cost will be:

c(x) = $1.25*x + $6 + $4 = $1.25*x + $10

And we have the restriction that Kalya can't spend more than $27.50

Then the cost must be equal or smaller than $27.50, we can write this as:

c(x) ≤ $27.50

$1.25*x + $10 ≤ $27.50

Whit the above equation we can find the maximum value of x if we isolate x in one side of the inequality.

$1.25*x + $10 ≤ $27.50

$1.25*x ≤ $27.50 - $10

$1.25*x ≤ $17.50

x ≤ ($17.50/$1.50)

x ≤ 11.67

So the maximum number of miles that she can travel on that uber is 11.67 miles, but in this cases we only work with whole numbers, so we should round it to the next whole number that meets the condition, which is 11.

x = 11

The maximum number of miles that she can travel on that uber is 11 miles.