word完整版)2012年AMC8竞赛真题及答案,推荐文档

1、2012年AMC8竞赛真题（英文版）1. uses ：3 pounds of meat to S hribiirpr Jhr Jier ianuly. Hnwniatn1 口uun血 of meal du強些he need to tnake 24 haiiibur宜吐屁 Ibr a nei.giborhood picnic?(A) G(C) ?1(D) S (E) 02. tn the Qnunty of East Weatmore, statisticians estimate there is a baby born every8 hciir and n cirth “ 眉叮 rlay T

2、ti tH产门八注代刘 hunrirfxL how rnariy pplc irc aidetl tu Lite pupulAtiun of Ell WvsLiiK)re tacli yem?(A) (B) TOO (C) SOO (D) 900(E) UW3. On Ftebruary 13 77)f OMiosh 幷訥管1皿减肝 listed the length oF daylight as 10 bourn and 2A minute the sirnrhe 毎 6；57 aM, nd the sunset 8：lf PMP The knih tifi sunriso wrt cTTi

3、, but the sunset wrts wiYing WLttidid the eilq really sbU(A) 5:W ?M (B) 5:21 pm (C) 5:41 Pi(D) 5;57 pm E)躲加 pm4. IJe4jecs faxnily ordered a 12-slice pizz for dinner Peter ate one slice and 或Rred aiHi-dhT slice DquM” wit h hi# bmiher 卩;uil rhai rnicti()n of tiio piyza did Frter cal ?5. In the diagram

4、, all angles are right angles and the lengths of the sides are given in centimeters. Note the diagram is not drawn to scale：. What is X ? in centimeters?(A) 1(B)2(C)3(D)4(E)5G A rectangular photograph is placed in a frame that forms a border two inches wide on all sides of the photograph The photogr

5、aph measures 8 inches high and 10 inches wide What is the area of the Ixjrder, in square inches?(A) 36(B) 40(C) 64(D) 72(E) 887. Isabella must take four 100-point tests in her math class. Her goal is to achieve an average grade of at Ie;ist 95 on the tests Ik?T first two les-t scores were 97 and 91.

6、 After swing her score on the third test, sae realized that site could still rearli her goal. What iu the lowest possible score she could have made on the third test?(A) 90(B) 02(C) 95(D) 96(E) 97& A shop advertises that everything is half price in todays sak/ In addition, a coupon gives a 20% disco

7、unt on sale prices. Using the coupon, the price today represents what percentage discount off the origina price?(A) 10(B) 3(C) 40(D) 60(E) 709. Tlie Fort Worth Zoo has a number of two-legged birds and a number of fourlegged iiiainnLals. On one visit to the zoo. Margie counted 2(X) heads and 522 legs

8、. How many of the animals that Margie counted were twolegged birds?(A) 61(B) 122(C) 139(D) 150(E) 1G110. How many 4-digit numbers greater than 1000 are there that use the four dibits of 2012?(A) 6(B) 7(C) 8(D) !)(E) 1211* Hie mean. median, and unique inodi of the positive integers 3. 4.久 15. G、7, t

9、are all equal What is the value of x?(A) 5(B) 6(C) 7(D) 11(E) 1212. What is the units digit of 132012 ?(A.) 1(B) 3(C)5(D) 7(E) 913. lanwr bought sonw pencils costing more than a penny each at the school book store and paid $1.43. Sliarena bought some of the same pencils and paid 81.87. How many more

10、 pencils did Sh arena buy than Jam ar?(A) 2(B) 3(C) 4(D) 5(E) 614. In Ulc BIG a middle school foolbsill conierence, each team pluys every other tFam exactly once. 汀 a total of 21 conference games were plawd during the 2012 season, how many teams were members of :he IMG X conference-7(A) 6(B) 7(C) 8(

11、D) 9(E) 1015. The smallest number greater than 2 that leaves a remainder of 2 when divided by ：L 4. 5, or 6 lies between what numbers?(A) 40 and 50(B) 51 and 55(C) 5G and 60(D) 61 and 6-5(E) 66 and 9916. Each of the digits 0. I. 2. 3. -I, 5. 6. J 5 and 9 is used only onoe to make two five-digit numb

12、ers so that they have the largest possible sum. Which of the following could be one of the numbers?(A) 76531(B) &6721(C) 87431(D) 96210(E) 97-10317. A square with an integer side length is cut into 10 squares, all of which have integer side length and at least 8 of which have area 1. What is the sma

13、llest possible value of the length of the side of the original square?(A) 3(B) 4(C) 5(D) 6(E) 71& What is the smaHest positive integer that is neither prime nor square and that has no prime factor lesss than 50?(A) 3127(B) SKJ3 (C) 3137(D) 3130(E) 311919. In a jar of reel, green, and blue marbles, a

14、ll but 6 arc red marbks, all but 8 are green, and all but 4 sire blue. How many marbles- are in the jar?(A) 6(D) 8(C) 9(D) 10(E) 1820. What is the correct ordering of the three mimbers 寻.齐，and 寻,in increasingorder?975f 579 9571 9 2321 W丿 192123 23 T9 21507759(D) 19 C 23 2l(E) 2l C 19 C 2321. Marla h

15、as a large white cube that has an edge of 10 feet. She also has enough green paint to cover 300 square feet. Marla use all the paint to create a wliite square entered on each face, surrounded by a green border What is the area of one of the whitr s(|uarcst in square feet?(A) 5丫勺(B) 10(C) 10V5(D) 50(

16、E) 50辺22. liet W be a set of nine distinct integers. Six of the elements nf the set are 2, 3. L G. 9. and 14. What is the number of possible values of the median of R?(A) 4(13)5(C) 6(D) 7(E) 823. An equilateral triangle and a regular hexagon hzw equal perimetfrs. H the area f the triangle is 1. what

17、 is the area of the hexagon?(A) 4(B) 5(C) 6(D) 4v幻(E) Gy 324. A circle of r“dius 2 is cut into four congruent arcs. The lour arcs arc joined to form the star figure shown What is the ratio of the area of the star figure to the area of the original circle?宁(B)7 V 4呼专25 A square with area 4 is inscribed in a square with area 5. with one vertex of the mailer square on each side of the larger square, A vertex of the sma