Human: Trevor and two of his neighborhood friends go to the toy shop every year to buy toys. Trevor always spends $20 more than his friend Reed on toys, and Reed spends 2 times as much money as their friend Quinn on the toys. If Trevor spends $80 every year to buy his toys, calculate how much money in total the three spend in 4 years. Assistant:
If Trevor spends $20 more than Reed every year to buy toys, Reed spends $80-$20 =$60.
Since Reed uses $60 every year to buy toys, his friend Quinn uses 60/2 = $30 every year to buy toys.
The total amount of money the three spend in a year together to buy toys is $30+$60+$80 = $170.
The total amount of money the three will use to buy toys in 4 years is $170*4 = $680.