Question

Lara employed a residential cleaning service to tidy up her home. They charged her $150 for 3

hours of work. Her neighbor, Roy hired the same agency and paid them $225 for their services.
How many hours did they take to complete the job at Roy's home?

Answer 1

Explanation:

Find the rate that was charged for Lara's time

rate = dollars / hour

The use this rate to calculate how many hours it took to clean Roy's house, since the rates are the same. Solve for hours.....

rate for Lara = dollars / hour = $150 / 3 hour = $50 / hour

rate for Roy = dollars / hour Solve for hours

multiply both sides by hours

(rate for Roy) (hour) = (dollars / hour) (hour)

(rate for Roy) (hour) = (hour) (dollars / hour) right side hours cancel

(rate for Roy) (hour) = (dollars) divide both sides by (rate for Roy)

(rate for Roy) (hour) / (rate for Roy) = (dollars) / (rate for Roy)

now the rate for Roy on the leftside cancel

(rate for Roy) (hour) / (rate for Roy) = (dollars) / (rate for Roy)

(hour) = (dollars) / (rate for Roy) Plug in $225 charged to Roy

and the $50 / hour rate

hour = $225 / ($50/hour) ( 1 over 1 / hour ) = hour

= $(225/50) hour think about 1 / (1/2) = 2 the same with units

hour = 4.5 hours