Derek finally gets his own allowance. He puts $2 away in January, $4 away in February, $8 away in March, $16 away in April and follows this savings pattern through to December. How much money does he have to spare and save by December?
Let's think: Derek doubles his allowance savings each month, so in May, Derek has $16 * 2 = $32. In June, Derek has $32 * 2 = $64. In July, Derek has $64 * 2 = $128. In August, Derek has $128 * 2 = $256. In September, Derek has $256 * 2 = $512. In October, Derek has $512 * 2 = $1024. In November, Derek has $1024 * 2 = $2048. By December, Derek has $2048 * 2 = $4096 to save.. The answer is: 4096.

John buys game loot boxes for $5 each. The average value of items inside is $3.5. He spends $40 on loot boxes. What is the average amount he lost?
Let's think: He bought 40 / 5 = 8 boxes. He loses an average of 5 - 3.5 = $1.50 per box. So he loses an average of 1.5 * 8 = $12.. The answer is: 12.

The price of a book was $400. If the book's price is decreased by 15% and then increased by 40%, what is the final price of the book?
Let's think: When the price of the book is decreased by 15%, the total price decrease is 15 / 100 * $400 = $60. The new price of the book becomes $400 - $60 = $340. The price of the book is then increased by 40 / 100 * 340 = $136. The final price of the book is $340 + $136 = $476.. The answer is: 476.

Brandon has been fired from half the businesses in town and has quit from a third of them. If there are 72 business in town, how many businesses can he still apply to?
Let's think:
First divide the total number of businesses by 2 to find how many businesses Brandon hasn't been fired from: 72 businesses / 2 = 36 businesses. Then divide the total number of businesses by 3 to find how many businesses Brandon quit from: 72 businesses / 3 = 24 businesses. Then subtract that number from the number of businesses he hasn't been fired from to find the number of businesses where he can still apply: 36 businesses - 24 businesses = 12 businesses.. The answer is: 12.