A taxicab charges $4.25 for the first mile and $1,50 for each additional mile. Write a rule for describing the total rater as a function of the total miles m. What is the taxi rate for 12 miles?

1 Answer
Oct 27, 2016

#"Total charge "=$4.25+$1.50(m-1)#

#"Total charge for 12 miles " =" "$20.75 #

Explanation:

#color(blue)("Building the rule")#

The trick with algebra is to think what you would do with numbers, then substitute letters.

Mile number 1 costs #$4.25#

The rest of the miles #=>("total miles "-1)xx$1.50#

Putting this all together we have:

#$4.25 +("total miles "-1)xx$1.50#

The question instructs that we are to use the letter m for the total miles so we now have:

#$4.25 +(m-1)xx$1.50#

This would be written as:

#$4.25 +$1.50(m-1)#

So #" Total charge "=$4.25+$1.50(m-1)#

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#color(blue)("Determine the charge for 12 miles")#

#" Total charge "=$4.25+$1.50(12-1)#

#" Total charge "=$4.25+$1.50(11)#

#" Total charge for 12 miles "=$4.25+$16.50" " =" "$20.75 #