Step-by-step reasoning process: She needs to buy 15 / 3 = 5 pizzas. The pizzas cost 5 * $12 = $60 total. It will take her $60 / $4 = 15 nights worth of babysitting to afford the pizza.
The question and answer:
Question and answer: Nelly wants to buy pizza for herself and her 14 friends. Each pizza costs $12 and can feed 3 people. If Nelly earns $4 a night babysitting the neighbors' kids, how many nights will she have to babysit to afford the pizza?
The answer is 15

Step-by-step reasoning process: Jeff has 16 - 4 = 12GB left over on his phone. Therefore, he has 12 * 1000 = 12,000MB. Therefore, he can store 12,000 / 30 = 400 songs.
The question and answer:
Question and answer: Jeff has 16 GB of storage on his phone. He is already using 4 GB. If a song takes up about 30MB of storage, how many songs can Jeff store on his phone? (There are 1000 MB in a GB).
The answer is 400

Step-by-step reasoning process: He burns 2 * 300 = 600 calories an hour. He dances for .5 * 2 = 1 hour per day. So he burns 600 * 1 = 600 calories per day. So he burns 600 * 4 = 2400 calories per week.
The question and answer:
Question and answer:
James takes up dancing for fitness. He loses twice as many calories per hour as he did when he was walking. He dances twice a day for .5 hours each time and he does this 4 times a week. He burned 300 calories an hour walking. How many calories does he lose a week from dancing?
The answer is 2400