Reasoning and answer: 15% of $300 is (15 / 100) * $300 = $45. Emma will earn an annual ROI of $45 for 2 years for a total of $45 * 2 = $90. 10% of $500 is (10 / 100) * $500 = $50. Briana will earn an annual ROI of $50 for 2 years for a total of $50 * 2 = $100. The difference between their ROI after 2 years is $100 - $90 = $10.
The answer: 10
What was the question?
Question: Emma and Briana invested some capital into a business. Emma's investment is supposed to yield 15% of the capital annually while Briana's should yield 10% annually. If Emma invested $300 and Briana invested $500, what will be the difference between their return-on-investment after 2 years?

Reasoning and answer: Rick has ironed 4 x 3 = 12 dress shirts. He has ironed 3 x 5 = 15 dress pants. In total, he has ironed 12 + 15 = 27 pieces of clothes.
The answer: 27
What was the question?
Question: Rick can iron 4 dress shirts in an hour. He can iron 3 dress pants in an hour. If he spends 3 hours ironing dress shirts and 5 hours ironing dress pants, how many pieces of clothing has he ironed?

Reasoning and answer: Each of Tom's visits was 200 * .7 = $140 cheaper. So he paid $200 - $140 = $60 per visit. That means he paid $60 * 2 = $120. So he saved $200 - $120 = $80.
The answer: 80
What was the question?
Question:
Tom cannot afford a normal doctor, so he goes to a discount clinic that is 70% cheaper. It takes two visits, though, instead of 1. A normal doctor charges $200 for a visit. How much money does he save?