How do you write each real-world example as a rate using labels and then the unit rate: Mrs. Thomas charges $60 for 120 minutes of tutoring? 1 Answer Feb 27, 2017 See the explanation Explanation: Let time be $t$Let cost be $c$Basing unity to be time The units of measurement for time in the question is given as minutes. $\textcolor{b r o w n}{\text{So using the same unites as in the question we have:}}$Using ratio: ("cost")/("time") ->c/t=($60)/120

To make unit time we need to convert the 120 minutes into 1 minute

So we have: ($60.00-:120)/(120-:120) = ($0.50)/1

For unit time to be 1 minute the charge is $0.50 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ $\textcolor{b r o w n}{\text{However, unit charge is normally stated as cost per hour. }}$So to change this to that form we need 60 minute ($0.50xx60)/(1xx60) = ($30)/(60" minute") But 60 minutes is the same as 1 hour giving: ($30)/(1" hour")