Question: A school has 100 students. Half of the students are girls, the other half are boys. 20% of the girls have dogs at home and 10% of the boys have dogs at home. How many students own dogs?
Answer: Out of 100 students, half are girls and half are boys so there are 100 / 2 = 50 girls. There are 50 girls out of 100 students means there are 100 - 50 = 50 boys. 20% of the 50 girls have dogs so they have .20 * 50 = 10 dogs. 10% of the 50 boys have dogs so they have .10 * 50 = 5 dogs. The girls have 10 dogs and the boys have 5 dogs so together, they have 10 + 5 = 15 dogs. The answer is 15.
[Question]Brenda is a vet who needs to spay some cats and twice as many dogs. If she needs to spay 21 animals total today, how many cats does she need to spay?
[Answer]Let c be the number of cats Brenda needs to spay and d be the number of dogs. We know that c + d = 21 and d = 2c. Substituting the second equation into the first, we get c + 2c = 21. Combining like terms, we get 3c = 21. Dividing both sides by 3, we get c = 7. The answer is 7.
Q: Suki bought 6.5 bags of coffee beans that each weighed 22 kilograms. Jimmy bought 4.5 bags of coffee beans that each weighed 18 kilograms. Suki and Jimmy combined their coffee beans and then repackaged them into 8-kilogram containers. How many containers did they use?
A: Suki = 6.5 * 22 = 143 kg. Jimmy = 4.5 * 18 = 81 kg. 143 + 81 = 224. 224 / 8 = 28. They used 28 containers. The answer is 28.
Question: James decides to start making his own coffee. He buys a coffee machine for $200 and gets a $20 discount. He figures it will cost him $3 a day to make his coffee. He previously bought 2 coffees a day for $4 each.  How long until the machine pays for itself?
Answer: He bought the machine for $200 - $20 = $180. He used to spend 4 * 2 = $8 a day. So he saves $8 - $3 = $5 a day. So it will take him $180 / $5 = 36 days to pay for itself. The answer is 36.
[Question]At 30, Anika is 4/3 the age of Maddie. What would be their average age in 15 years?
[Answer]If Anika is 30 now, in 15 years, she'll be 30 + 15 = 45 years old. At 30, Anika is 4 / 3 the age of Maddie, meaning Maddie is 4 / 3 * 30 = 40 years. In 15 years, Maddie will be 40 + 15 = 55 years old. Their total age in 15 years will be 55 + 45 = 100. Their average age in 15 years will be 100 / 2 = 50. The answer is 50.
[Question]Ali is a baker. Leila ordered 3 chocolate cakes for $12 each and 6 strawberry cakes for $22 each. How much should Leila pay Ali?
[Answer]
For the chocolate cakes: Leila should pay: 12 * 3 = $36. For the strawberry cakes: Leila should pay: 22 * 6 = $132. Combining the chocolate cakes and strawberry cakes, Leila should pay: 36 + 132 = $168. The answer is 168.