Jack orders 3 sandwiches that cost $5 each. He pays with a $20 bill. How much does he get in change? Give the rationale and then the answer.
Let's think step by step. The cost was 3 * 5 = $15. So he got 20 - 15 = $5 in change.. The answer is: 5.

Tom eats a pound of carrots and twice as much broccoli. If carrots have 51 calories per pound and broccoli has 1/3 that many calories, how many calories did he eat in total? Give the rationale and then the answer.
Let's think step by step. He ate 2 * 1 = 2 pounds of broccoli. There are 51 / 3 = 17 calories in each pound of broccoli. So he ate 2 * 17 = 34 calories of broccoli. He ate 1 * 51 = 51 calories of carrots. So in total he ate 51 + 34 = 85 calories.. The answer is: 85.

Sebastian plays drums for percussion in an orchestra. He sits next to the brass section where four people play trombone, two play trumpet, and one plays a French horn. In front of them are the strings section with three violinists, a cellist, and a contrabassist. Next to the strings are a trio of clarinets and a quartet of flute players in the woodwinds section. The maestro conducts them all. How many people are in the orchestra? Give the rationale and then the answer.
Let's think step by step. Sebastian in the percussion section makes 1 person. The brass section has 4 + 2 + 1 = 7 people. The strings section has 3 + 1 + 1 = 5 people. The woodwinds section has 3 + 4 = 7 people. The maestro is 1 person. Thus, the orchestra has 1 + 7 + 5 + 7 + 1 = 21 people in it.. The answer is: 21.