10 people attended class on Monday, 15 on Tuesday, and 10 on each day from Wednesday through Friday. What was the average number of people who attended class each day?
Let's think: A total of 10 + 15 + 10 + 10 + 10 = 55 people attended class across the 5 days. An average of 55 people / 5 days = 11 people per day attended class.. The answer is: 11.

Calen originally had 5 more pencils than does Caleb, and Caleb has 3 less than twice as many pencils as does Candy. If Calen lost 10 pencils, which left him with 10 pencils, then how many pencils does Candy have?
Let's think: If Calen lost 10 pencils, which left him with 10 pencils, then Calen originally had 10 + 10 = 20 pencils. Calen originally had 5 more pencils than does Caleb, and thus Caleb has 20 - 5 = 15 pencils. Let's let "x" represent the number of pencils owned by Candy. Since Caleb has 3 less than twice as many pencils as does Candy, then (2 * x) - 3 = 15. This simplifies to 2 * x = 18. Thus, the number of pencils owned by Candy is x = 9 pencils.. The answer is: 9.

Cleo and Ignacio placed 30 of their marbles in a jar on a Monday. They took 3/5 of the marbles from the jar the next day and divided them equally. On the third day, Cleo took 1/2 of the marbles remaining in the jars. How many marbles did Cleo have on the third day?
Let's think: On the first day, Cleo and Ignacio took 3 / 5 * 30 marbles = 18 marbles from the jar. When they shared the marbles, each got 18 marbles / 2 people = 9 marbles / person. The total number of marbles remaining in the jar is 30 marbles - 18 marbles = 12 marbles. On the third day, Cleo took 1 / 2 * 12 marbles = 6 marbles from the jar. The total number of marbles she has on the third day is 6 marbles + 9 marbles = 15 marbles.. The answer is: 15.

Mary has 5 green crayons and 8 blue crayons of different shades. If she gives out 3 green crayons and 1 blue crayon to Becky, how many crayons does she have left?
Let's think:
She had 5 + 8 = 13 crayons to start with. She gave out 3 + 1 = 4 crayons to Becky. She will have 13 - 4 = 9 crayons left.. The answer is: 9.