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1、Problem 1Margie bought apples at a cost of cents per apple. She paid with a 5-dollar bill. How much change did Margie recieve? Solutioncents is equivalent to Then the three apples cost The change Margie receives is Problem 2Karls rectangular vegetable garden is feet by feet, and Makennas is feet by
2、feet. Whose garden is larger in area? SolutionThe area of a rectangle is given by the formula length times width. Karls garden is square feet and Makennas garden is square feet. Since Makennas garden is larger by square feet. Problem 3Extend the square pattern of 8 black and 17 white square tiles by
3、 attaching a border of black tiles around the square. What is the ratio of black tiles to white tiles in the extended pattern?SolutionOne way of approaching this is drawing the next circle of boxes around the current square. We can now count the number of black and white tiles; 32 black tiles and 17
4、 white tiles. This means the answer is . Problem 4Here is a list of the numbers of fish that Tyler caught in nine outings last summer: Which statement about the mean, median, and mode is true? SolutionFirst, put the numbers in increasing order. The mean is the median is and the mode is Because, the
5、answer is Problem 5What time was it minutes after midnight on January 1, 2011? SolutionThere are minutes in an hour. or hours and minutes. There are hours in a day, so the time is hours and minutes after midnight on January 2, 2011. Problem 6 In a town of adults, every adult owns a car, motorcycle,
6、or both. If adults own cars and adults own motorcycles, how many of the car owners do not own a motorcycle? Solution 1By PIE, the number of adults who own both cars and motorcycles is Out of the car owners, of them own motorcycles and of them dont. Solution 2There are total adults, and own a motorcy
7、cle. The number of adults that dont own a motorcycle is . Since everyone owns a car or motorcycle, one who doesnt own a motorcycle owns a car, so the answer is . Problem 7Each of the following four large congruent squares is subdivided into combinations of congruent triangles or rectangles and is pa
8、rtially bolded. What percent of the total area is partially bolded? SolutionAssume that the area of each square is one. Then, the area of the shade region in the top left square is 1/4. The area of the top right shaded region is 1/8. The area of the bottom left shaded region is 3/8. And the area of
9、the bottom right shaded region is 1/4. Add the four fractions: 1/4 + 1/8 + 3/8 + 1/4 = 1. The four squares together have an area of 4, so the percent is 1/4 = 25%. Therefore the solution is Problem 8Bag A has three chips labeled 1, 3, and 5. Bag B has three chips labeled 2, 4, and 6. If one chip is
10、drawn from each bag, how many different values are possible for the sum of the two numbers on the chips? SolutionBy adding a number from Bag A and a number from Bag B together, the values we can get are Therefore the number of different values is . You can also approach this problem by noticing the
11、sums will make odd multiples from to inclusive. Problem 9Carmen takes a long bike ride on a hilly highway. The graph indicates the miles traveled during the time of her ride. What is Carmens average speed for her entire ride in miles per hour? SolutionWe observe the graph and see that the shape of t
12、he graph does not matter. We only want the total time it took Carmen and the total distance she traveled. Based on the graph, Carmen traveled 35 miles for 7 hours. Therefore, her average speed is Problem 10The taxi fare in Gotham City is $2.40 for the first mile and additional mileage charged at the
13、 rate $0.20 for each additional 0.1 mile. You plan to give the driver a $2 tip. How many miles can you ride for $10? SolutionLet be the number of miles you ride. The number of miles you ride after the first half mile is We can write this equation: Problem 11 The graph shows the number of minutes stu
14、died by both Asha (black bar) and Sasha (grey bar) in one week. On the average, how many more minutes per day did Sasha study than Asha? SolutionAverage the differences between each day. We get . We find the average of this list to get Problem 12Angie, Bridget, Carlos, and Diego are seated at random
15、 around a square table, one person to a side. What is the probability that Angie and Carlos are seated opposite each other? Solution 1If we designate Angie to be on a certain side, then all placements of the other people can be considered unique. There are then total seating arrangements. If Carlos is across from Angie, there are only ways to fill the remain
