Nigella is a realtor who earns a base salary of $3,000 a month plus a 2% commission on every house she sells. One month, Nigella sells 3 houses and earns $8,000 total. House B costs three times as much as House A. House C cost twice as much as House A minus $110,000. How much did House A cost?
Let's think: First figure out how much money Nigella earned from commission by subtracting her base salary from her total earnings: $8,000 - $3,000 = $5,000. Next, figure out how much all three houses cost by dividing Nigella's commission money by her commission rate: $5,000 0.02 = $250,000. Next, express each house's price in terms of A's price: B = 3A, and C = 2A - $110,000. Now we know that A + 3A + 2A - $110,000 = $250,000. We can combine like terms to find that 6A - $110,000 = $250,000. Now we add $110,000 to both sides of the equation and get 6A = $360,000. We can divide both sides by 6 to find A = $60,000.. The answer is: 60000.

A mechanic charges $60 an hour to repair a car. He works 8 hours a day for 14 days on one car. The mechanic also used $2500 in parts. How much did the car's owner have to pay?
Let's think: The mechanic worked 8 * 14 = 112 hours. So the labor cost 60 * 112 = $6720. That means the total cost was 6720 + 2500 = $9220.. The answer is: 9220.

9 years from now, John will be 3 times as old as he was 11 years ago. How old is he now?
Let's think: Let J represent John's age. We have J + 9 = 3(j 11). So, J + 9 = 3J 33. So, 9 = 2J 33. So, 42 = 2J. Which means that John's age is J = 42 / 2 = 21.. The answer is: 21.

David swims the 100-meter freestyle in 48 seconds. He swims the 100-meter backstroke 4 seconds slower than he swims the 100-meter freestyle, he swims the 100-meter butterfly 3 seconds slower than he swims the 100-meter backstroke, and he swims the 100-meter breaststroke 2 seconds slower than he swims the 100-meter butterfly. What is the combined length of time, in seconds, it would take for him to swim all four 100-meter events (the freestyle, the backstroke, the butterfly, and the breaststroke)?
Let's think:
David swims the 100m backstroke at 48 + 4 = 52 seconds. He swims the 100m butterfly at 52 + 3 = 55 seconds. He swims the 100m breaststroke at 55 + 2 = 57 seconds. IN total, it would take David 48 + 52 + 55 + 57 = 212 seconds.. The answer is: 212.