Question: Tim buys a book of esoteric words. He learns 10 words from it a day. In 2 years the book has increased the number of words he knows by 50%. How many words did he know originally?
Answer: In 2 years there are 365 * 2 = 730 days. So he has learned 730 * 10 = 7300 words. He knew 1 / .5 = 2 times that number of words before the book. So he knew 7300 * 2 = 14600 words before. The answer is 14600.

Question: While driving up a road, Philip passed through 5 intersections. 4 crosswalks marked each intersection with a total of 20 lines per crosswalk. Calculate the total number of lines of the crosswalks in the five intersections.
Answer: If one intersection has 4 crosswalks, with 20 lines per crosswalk, there are 20 * 4 = 80 lines in all the crosswalks per intersection. If there are 5 intersections, the total number of lines in all the intersections is 80 * 5 = 400 lines. The answer is 400.

Question: Joan has 180 socks. Two thirds of the socks are white, and the rest of the socks are blue. How many blue socks does Joan have?
Answer: Joan has (180 / 3) * 2 = 120 white socks. The number of blue socks Joan has is 180 - 120 = 60. The answer is 60.

Question: John adopts a dog from a shelter. The dog ends up having health problems and this requires 3 vet appointments, which cost $400 each. After the first appointment, John paid $100 for pet insurance that covers 80% of the subsequent visits. How much did he pay in total?
Answer:
He got a discount of 400 * .8 = $320. He got that discount for 3 - 1 = 2 visits. So each of those visits cost 400 - 320 = $80. So he paid 2 * 80 = $160 for those visits. That means he paid a total of 400 + 160 + 100 = $660. The answer is 660.