2012 澳洲 AMC D-Intermediate 真题 答案 详解

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中英双语真题

Intermediate Paper (9-10 Grade)

1-10 questions, 3 points each

1. Calculate (8 \times 3.3)
2. (A) 24.24
3. (B) 24.4
4. (C) 25.4
5. (D) 26.24

6. (E) 26.4

7. Xiaofang's remaining allowance after three weeks is $20, spending a total of $1 on drinks during this period. What was her average weekly allowance?

8. (A) $5
9. (B) $7
10. (C) $9
11. (D) $20

12. (E) $21

13. In the diagram below, find the measure of ∠PQR.

14. (A) 40°
15. (B) 50°
16. (C) 60°
17. (D) 70°

18. (E) 80°

19. A number multiplied by (\frac{3}{5}) equals 48. Find that number.

20. (A) 54
21. (B) 60
22. (C) 64
23. (D) 80

24. (E) 84

25. What number divided by 6 results in (\frac{1}{3})?

26. (A) 18
27. (B) (\frac{1}{2})
28. (C) (\frac{1}{18})
29. (D) 2

30. (E) 9

31. Given the average of five numbers: x, 1, (\frac{1}{2}), (\frac{1}{3}), (\frac{1}{4}) is 1. Find the value of x.

32. (A) (\frac{1}{5})
33. (B) (\frac{2}{3})
34. (C) (\frac{11}{5})
35. (D) (\frac{25}{12})
36. (E) (\frac{35}{12})

英文真题

Intermediate Division
Questions 1 to 10, 3 marks each

1. The value of $8 \times 3.3$ is
   (A) 24.24 (B) 24.4 (C) 25.4 (D) 26.24 (E) 26.4

2. Sally has $20 of her pocket money left after 3 weeks, having spent just $1 on a drink. How much pocket money does she get each week?
   (A) $5 (B) $7 (C) $9 (D) $20 (E) $21

3. In the diagram, the size of $\angle PQR$ is
   (A) 40° (B) 50° (C) 60° (D) 70° (E) 80°

4. Three-fifths of a number is 48. What is the number?
   (A) 54 (B) 60 (C) 64 (D) 80 (E) 84

5. By what number must 6 be divided to obtain $\frac{1}{3}$ as a result?
   (A) 18 (B) $\frac{1}{2}$ (C) $\frac{1}{18}$ (D) 2 (E) 9

6. The average of the five numbers $x$, $1$, $\frac{1}{2}$, $\frac{1}{3}$ and $\frac{1}{4}$ is 1. The value of $x$ is
   (A) $\frac{1}{5}$ (B) $\frac{2}{3}$ (C) $\frac{11}{5}$ (D) $\frac{25}{12}$ (E) $\frac{35}{12}$

真题文字详解(英文)

SOLUTIONS - INTERMEDIATE DIVISION 1. The value of $8 \times 3.3$ is 26.4, hence (E). 2. After three weeks Sally has $20 left and has spent $1 on a drink, so had $21 dollars in three weeks. This is $7 pocket money per week, hence (B). 3. Filling in the angles as shown, as PR is a straight line and the angle sum of △PQR is 180°, we have ∠PQR = 180° − 60° − 50° = 70°, hence (D). 4. (Also J6) Alternative 1 We have $\frac{3x}{5} = 48$, so $3x = 5 \times 48$ and $x = 5 \times 16 = 80$, hence (D). Alternative 2 Three-fifths of the number is 48, so one-fifth of the number is $48 \div 3 = 16$ and the number is $5 \times 16 = 80$, hence (D). 5. (Also J10 & S2) We have $\frac{6}{x} = \frac{1}{3}$, so $x = 18$, hence (A). 42