Answer the following question.
A yearly book sale is held in school where students can sell their old books at a cheaper price. Two-fifths of Lovely's books can be sold for $2.50 each and the rest for $2 each. How much will Lovely earn if all 10 books were sold?
Step-by-step reasoning process: Lovely will sell 10 x 2 / 5 = 4 books for $2.50 each. She will sell 10 - 4 = 6 books for $2 each. Her earnings for the 4 books at $2.50 will be $2.50 x 4 = $10. Her earnings for the 6 books for $2 each will be $2 x 6 = $12. Thus, Lovely's total earning if all 10 books are sold is $10 + $12 = $22.
The answer is 22.

Answer the following question.
William washes cars as a side job. He typically spends 4 minutes washing a car’s windows, 7 minutes washing the car body, 4 minutes cleaning the tires, and 9 minutes waxing the car. This morning he washed 2 normal cars and one big SUV, which took twice as long as a normal car. How many minutes did William spend washing all the vehicles?
Step-by-step reasoning process: William spends 4 + 7 + 4 + 9 = 24 minutes washing a normal car. He washed 2 normal cars, so he spent 24 * 2 = 48 minutes on the normal cars. He took twice as long as one car for the SUV, so he took 24 * 2 = 48 minutes on the SUV. Thus, William spent 48 + 48 = 96 minutes washing all the vehicles.
The answer is 96.

Answer the following question.
Darryl is an inventor who just designed a new machine. He had to pay $3600 for the parts to construct the machine, and $4500 for the patent he applied for once he built it. If the machine sells for $180, how many machines does Darryl need to sell to break even after the costs?
Step-by-step reasoning process: Darryl paid 3600 + 4500 = $8100 in costs for the parts and patent. Thus, Darryl needs to sell 8100 / 180 = 45 machines to break even.
The answer is 45.

Answer the following question.
Luke takes a 70-minute bus to work every day. His coworker Paula takes 3/5 of this time to arrive by bus at work. If Luke takes a bike ride back home every day, 5 times slower than the bus, and Paula takes the bus back home, calculate the total amount of time, in minutes, they take traveling from home to work and back each day.
Step-by-step reasoning process: When Luke takes the 70 - minute bus to work, his coworker Paula takes 3 / 5 * 70 = 42 minutes to travel from home to work. From work to home, Paula spends the same amount of time she spent going to work, giving a total of 42 + 42 = 84 minutes in a day traveling. From work to home, while riding the bike, Luke spends 5 * 70 = 350 minutes on the road. The total time Luke takes to travel from home to work and back is 350 + 70 = 420 minutes. Together, Luke and Paula takes 420 + 84 = 504 minutes.
The answer is 504.