Three paper bags contain a total of 24 apples. The first and second bags contain a total of 11 apples. The second and third bags contain a total of 18 apples. How many apples are in the first and third bags together?

A worm has fallen into a hole that is 26 inches deep. It climbs up 8 inches and slides back 3 inches every day. How many days will it take the worm to reach the top?

Rita, Peter, and Skeeter are penguins. They weigh 90 pounds altogether. Rita and Peter know they weigh the same amount. Peter and Skeeter know they weigh 68 pounds together. How much does Skeeter weigh?

A new store opened up at the mall. During the first hour, 94 people came in and 27 people left. During the second hour, 18 people came in and 9 people left. How many people were still in the store after 2 hours?

Ben had some baseball cards. His friend, Tim, had 20 cards. After Ben bought 3 more cards, he had twice as many cards as Tim. How many cards did Ben have at first?