Q: There are 30 students in Ms. Leech's class. Twice as many girls as boys are in the class. There are 10 boys in the class and each boy today brought 5 cups for science activity class as Ms. Leech had instructed. If the total number of cups brought by the students in the class is 90, how many cups did each girl bring?
A: If there are 30 students in Ms. Leech's class, and the number of boys is 10, the number of girls in Ms. Leech class is 30 - 10 = 20. If each boy brought 5 cups for the science activity, the total number of cups brought by the boys is 5 * 10 = 50 cups. The number of cups that the girls brought is 90 - 50 = 40 of the total number. Since the number of girls in the class is 20, each girl brought 40 / 20 = 2 cups each. The answer is 2.

Q: Andy had a platter of chocolate cookies. He ate 3 of them then gave his little brother 5 because he was behaving. He then handed the platter to his basketball team of eight members. The first player to arrive took 1, the second player to arrive took 3, the third player took 5, and so on. When the last player took his share, the platter was empty. How many chocolate cookies did Andy have from start with?
A: Andy and his brother ate 5 + 3 = 8 cookies in total. The nth term of the sequence for the basketball players taking cookies in 2n - 1. The number of players is 8 so they would have eaten 1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 = 64 cookies. In total Andy had 64 + 8 = 72 cookies to start with before they were all eaten. The answer is 72.

Q: Ginger is weaving mats out of colored straw. Each mat takes 20 red straws, 30 orange straws, and half as many green straws as orange straws. How many straws does she need to make 10 mats?
A:
First find the number of green straws each mat needs: 30 orange straws / 2 orange straws / green straw = 15 green straws. Then find the total number of straws in each mat: 15 straws + 20 straws + 30 straws = 65 straws. Then multiply that number by the number of mats to find the total number of straws Ginger needs: 65 straws / mat * 10 mats = 650 straws. The answer is 650.