1) A girl bought a dog for $10, sold it for $15, bought it back for $20, and finally sold it for $25. Did the girl make or lose money, and how much did she make or lose?
2) The average of five weights is 13 grams. This set of five weights is then increased by another weight of 7 grams. What is the average of the six weights?
3) Each of the boxes in the figure is a square. How many different squares can be traced using the lines in the figure?
1) She paid out $10 + $20 = $30. She received $15 + $25 = $40. She made $10.
2) The average of the five weights is 13 grams. Then the total weight of the five weights is 5 x 13 or 65 grams. The sixth weight increases the total to 72 grams. The average of the six weights is
72/6 or 12 grams.
3) There are three different sizes for the squares that can be traced in the figure: 1 x 1, 2 x 2, and 3 x 3. The table shows how many squares can be traced for each size.