11
an electrician charges a call-out fee of $40 and $60
per hour.
a. write an expression for the total cost if the
electrician works for h hours
b. how much would it cost if a particular job took
3 hours?
c. use your expression to work out how many hours
the electrician worked for if he charged $400 for a
particular job.

When visiting his parents, tyler drives at an average speed of 42 km/h through urban areas, and at an average speed of 105 km/h along the motorway. his journey usually takes him 2.5 hours. one day when there is a fog, he sets off 1 hour early and only manages to average 28 km/h in urban areas and 60 km/h on the motorway. he arrives 30 minutes late. how long was tyler journey?