1. D: The total number of feet he ascended can be determined by adding 482 feet and 362 feet. The sum of 482 and 362 is 844. Thus, he ascended 844 feet in all.
2. C: The item priced at $4.58 can be rounded to $5. The item priced at $6.22 can be rounded to $6. The item priced at $8.94 can be rounded to $9. The sum of 5, 6 and 9 is 20. Thus, the best estimate is $20.
3. C: In order to find the amount donated the following year, you multiply the amount donated the previous year by 3. Thus, the amount donated the second year was $6 (). The amount donated the third year was $18 (). The amount donated the fourth year was $54 (The amount donated the fifth year was $162 ().
4. D: If she drinks 8 glasses of water each day, the number of glasses of water she drinks in 12 days can be determined by multiplying 8 by 12. This product is 96; thus she drinks 96 glasses of water in a 12-day time span. The relationship between the number of glasses of water she drinks per day and the total number of glasses of water she drinks in 12 days can be represented by an appropriate multiplication or division number sentence within the following fact family: Subtracting 8 from 12 will not reveal the number of glasses she drinks in a 12-day time span. The number sentence: , is not in this fact family.
5. C: If each rectangle has a length that is 5 cm more than that of the previous rectangle, the lengths of the 3rd rectangle through the 11th rectangle can be found by adding 5 cm to the length of the second triangle and continuing for each next rectangle. So, the lengths of the rectangles will be as follows: 16 cm, 21 cm, 26 cm, 31 cm, 36 cm, 41 cm, 46 cm, 51 cm, and 56 cm.
6. B: In order to find the number of cans of food he gave to the first charity, the number of cans of food he has left needs to be subtracted from the number of cans he collected; .
7. A: The sum of the two decimals is 10.80; the decimals are added just like whole numbers are, while aligning the decimal point.
8. B: She runs laps in all, or 96 laps.
9. B: The number of cupcakes sold can be rounded as follows: 80 cupcakes, 50 cupcakes, and 70 cupcakes, which sum to 200. Therefore, the best estimate for the number of cupcakes sold is 200 cupcakes.
10. B: The amount of money Carlisle charges per hair cut can be rounded to $20; . Thus, his total charges are approximately $600.
