Esteban finds 12 baseball cards on Monday and 24 more baseball cards on Tuesday. He gives some baseball cards to his sister, and now he has 13 baseball cards left. How many cards did he give to his sister?

Fabian harvests 10 pounds of tomatoes from his garden. he needs 225 pounds to make a batch of soup. if he sets aside 2.8 pounds of tomatoes to make spaghetti sauce, how many batches of soup can fabian make?

Asays "we are both knaves" and b says nothing. exercises 24–31 relate to inhabitants of an island on which there are three kinds of people: knights who always tell the truth, knaves who always lie, and spies (called normals by smullyan [sm78]) who can either lie or tell the truth. you encounter three people, a, b, and c. you know one of these people is a knight, one is a knave, and one is a spy. each of the three people knows the type of person each of other two is. for each of these situations, if possible, determine whether there is a unique solution and determine who the knave, knight, and spy are. when there is no unique solution, list all possible solutions or state that there are no solutions. 24. a says "c is the knave," b says, "a is the knight," and c says "i am the spy."

Determine the difference: 3.2 × 1010 – 1.1 × 1010. write your answer in scientific notation.