A farm has 100 chickens. 20 percent are Black Copper Marans, and 80 percent of the Black Copper Marans are hens. How many BCM hens are there?
Let's think: Black Copper Marans: 100(.20) = 20. BCM Hens:20(.80) = 16.. The answer is: 16.

Tara's taking a road trip for the weekend. She drives for two days, stopping to fill up her gas tank each time from empty to full when she needs it. She visits 4 different gas stations in total, with the price of gas being $3, $3.50, $4, and $4.50 respectively at each. If Tara's car has a 12-gallon tank, how much does she spend on gas for her road trip?
Let's think: The first station Tara stops at charges $3 for a gallon of gas, so for her 12 - gallon tank she spends 12 * 3 = 36 dollars. The second station Tara stops at charges $3.50 for a gallon of gas, so for her 12 - gallon tank she spends 12 * 3.5 = 42 dollars. The third station Tara stops at charges $4 for a gallon of gas, so for her 12 - gallon tank she spends 12 * 4 = 48 dollars. The fourth station Tara stops at charges $4.50 for a gallon of gas, so for her 12 - gallon tank she spends 12 * 4.5 = 54 dollars. Now that we know all the individual amounts, we add 36 + 42 + 48 + 54 = 180 dollars in gas in total.. The answer is: 180.

Stan hires a magician for $60 an hour. He works 3 hours every day for 2 weeks. How much money does he pay the magician?
Let's think: The magician works for 2 * 7 = 14 days. So the magician works 14 * 3 = 42 hours. So that means he pays 42 * 60 = $2520.. The answer is: 2520.

At a roller derby, 4 teams are competing. Each team is made up of 10 members, and each member needs a pair of roller skates to compete in and another pair of skates as a backup. None of the skates have laces yet, so each member is offered 3 sets of laces per pair of skates. How many sets of laces have been handed out?
Let's think:
There are a total of 4 teams * 10 members per team = 40 team members. Each person receives 1 pair of competing roller skates + 1 pair of backup roller skates = 2 pairs of roller skates. So there are a total of 40 team members * 2 pairs of roller skates per team member = 80 roller skates. There were therefore 80 roller skates * 3 sets of laces per pair of roller skates = 240 sets of laces handed out.. The answer is: 240.