2018 澳洲 AMC B-UpperPrimary 真题 答案 详解

中英双语真题

1-10 题，每题 3 分
Questions 1 to 10, 3 marks each

1. 请问下列哪一项内的数最接近 208?
   Which one of these numbers is closest to 208?
   (A) 190 (B) 200 (C) 205 (D) 210 (E) 218

2. 小佳原本有 $47，她又得到 $25 的生日礼金。请问她现在有多少钱？
   Callie has $47 and then gets $25 for her birthday. How much does she have now?
   (A) $52 (B) $62 (C) $65 (D) $69 (E) $72

3. 请问下列哪一项内的数是 8 的倍数？
   Which one of the following numbers is a multiple of 8?
   (A) 18 (B) 28 (C) 38 (D) 48 (E) 58

4. 小凯用字母串珠做出右侧这个项链。
   Kate made this necklace from alphabet beads.
   她将它翻面过来，展现出串珠的背面。请问下列哪一项内的图是现在看起来样子？
   She put it on the wrong way around, showing the back of the beads. What does this look like?
   (A) E T A K (B) Y A T E (C) E T A K (D) K A T E (E) E T A K

5. 请写出八仟八佰零八的阿拉伯数字。
   Write the number for eight thousand, eight hundred and eight.
   (A) 88008 (B) 80808 (C) 80088 (D) 888 (E) 8808

6. 小珍有一些 20 分的硬币而小德有一些 50 分的硬币。若他们两人有一样多的钱。请问他们两人的硬币总数量最少有多少枚？
   Jane has a number of 20c coins and Tariq has a number of 50c coins. They have the same amount of money. What is the smallest number of coins they could have all together?
   (A) 2 (B) 5 (C) 6 (D) 7 (E) 10

英文真题

Upper Primary Division
Questions 1 to 10, 3 marks each

1. Which one of these numbers is closest to 208?
   (A) 190 (B) 200 (C) 205 (D) 210 (E) 218

2. Callie has $47 and then gets $25 for her birthday. How much does she have now?
   (A) $52 (B) $62 (C) $65 (D) $69 (E) $72

3. Which one of the following numbers is a multiple of 8?
   (A) 18 (B) 28 (C) 38 (D) 48 (E) 58

4. Kate made this necklace from alphabet beads. She put it on the wrong way around, showing the back of the beads. What does this look like?
   (A) KATE (B) EKAT (C) ETAK (D) KATE (E) ETAX

5. Write the number for eight thousand, eight hundred and eight.
   (A) 88008 (B) 80808 (C) 80088 (D) 888 (E) 8808

6. Jane has a number of 20c coins and Tariq has a number of 50c coins. They have the same amount of money. What is the smallest number of coins they could have all together?
   (A) 2 (B) 5 (C) 6 (D) 7 (E) 10

真题文字详解(英文)

Solutions – Upper Primary Division
1. (Also MP6) 208 is between 205 and 210. Of these, the distance to 205 is 3 and the distance to 210 is 2. Therefore 210 is closer, hence (D).
2. (Also J2) She has 47 + 25 = 72 dollars, hence (E).
3. Multiples of 8 less than 60 are 8, 16, 24, 32, 40, 48 and 56. The only one of these listed in (A)-(E) is 48, hence (D).
4. (Also MP7, J4) The back of the necklace will look like the mirror image of the front of the necklace. So each letter will be mirrored, and the order of the letters will be reversed:
KATE | ƎTAX
front | back
hence (A).
5. Adding, 8000 + 800 + 8 = 8808, hence (E).
6. The amount of money they each have in cents is a multiple of both 20 and 50. The least common multiple of 20 and 50 is 100. So for the smallest number of coins, they have 100 cents each, and Jane has 5 coins and Tariq has 2. Then the total number of coins is 5 + 2 = 7, hence (D).
7. (Also MP11) Alternative 1 If she had 60 books, she would fill 5 shelves with 12 books each. Since she has 2 fewer, her last shelf has 10 books, hence (D).
Alternative 2 58 ÷ 12 = 4 r10 so that she fills 4 shelves with 12 books, with 10 books on the 5th shelf, hence (D).