Step-by-step reasoning process: The first 5 days cost 5 * 100 = $500. He gets 10 - 5 = 5 days on discount. He paid 5 * 60 = $300 at the discounted rate. So in total he pays 500 + 300 = $800.
The question and answer:
Question and answer: Tom charges a fee of $100 a day to search for an item for the first 5 days and then $60 per day for every day after that. How much did it cost for him to look for an item for 10 days?
The answer is 800

Step-by-step reasoning process: The binders cost 3 binders * $2 / binder = $6. The notebooks cost 6 notebooks * $1 / notebook = $6. The amount of Lea’s purchases is: $16 + $6 + $6 = $28.
The question and answer:
Question and answer: Léa bought one book for $16, three binders for $2 and six notebooks for $1. Calculate the total cost of her purchases.
The answer is 28

Step-by-step reasoning process: Bert was able to earn 8 x $18 = $144 for the toy phones. While Tory was able to earn 7 x $20 = $140 for the toy guns. Therefore, Bert was able to earn $144 – $140 = $4 more than Tory.
The question and answer:
Question and answer:
Bert was able to sell 8 toy phones for $18 each, while Tory was able to sell 7 toy guns for $20 each. How much more did Bert earn than Tory?
The answer is 4