Beth is a scuba diver. She is excavating a sunken ship off the coast of a small Caribbean island and she must remain underwater for long periods. Her primary tank, which she wears when she first enters the water, has enough oxygen to allow her to stay underwater for 2 hours. She also has several 1-hour supplemental tanks that she takes with her as well as stores on the ocean floor so she can change tanks underwater without having to come up to the surface. She will need to be underwater for 8 hours. How many supplemental tanks will she need?
Let's think: For an 8 - hour dive, she will use her 2 - hour primary tanks and will need supplemental tanks for 8 - 2 = 6 additional hours. Since each supplemental tank holds 1 hour of oxygen, for 6 hours she will need 6 / 1 = 6 supplemental tanks.. The answer is: 6.

Helga went shopping for a new pair of shoes. At the first store, she tried on 7 pairs of shoes. At the second store, she tried on 2 more pairs than at the first store. At the third store, she did not try on any shoes, but she did buy a scarf. But at the fourth store, she tried on twice as many pairs of shoes as she did at all three other stores combined, before finally choosing a pair to buy. What is the total number of pairs of shoes Helga tried on before buying her new shoes?
Let's think: At the second store, she tried on 7 + 2 = 9 pairs of shoes. Therefore, at the first three stores, she tried on 7 + 9 + 0 = 16 pairs of shoes. At the fourth store, she tried on 16 * 2 = 32 pairs of shoes. Thus, in total, she tried on 16 + 32 = 48 pairs of shoes.. The answer is: 48.

Johnny buys 15 packs of colored pencils for his class. Each pack has a red, yellow, and green pencil inside. When he gets home he notices that 3 of the packs have two extra red pencils inside. How many red colored pencils did Johnny buy?
Let's think: Johnny bought 15 packs, and every normal pack has 1 red pencil. He should have 15 * 1 = 15 red pencils. 3 of the packs have 2 extra red colored pencils, so there are 3 * 2 = 6 extra red pencils. In total, Johnny has 15 + 6 = 21 red colored pencils.. The answer is: 21.

Alex has 2 cakes that are each cut into 8 slices. A fourth of the slices are given away to his friends. A third of the remaining slices are given away to his family. Alex eats 3 slices. How many slices of the cake are left?
Let's think:
There are 2 * 8 = 16 slices of cake. There are 16 / 4 = 4 slices. There are 16 - 4 = 12 slices left. There are 12 / 3 = 4 slices given away. There are 12 - 4 - 3 = 5 slices of cake left.. The answer is: 5.