1997美国初中数学竞赛真题.docx

1997美国初中数学竞赛真题
1、
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2、Ahn chooses a two-digit integer, subtracts it from 200, and doubles the result. What is the largest number Ahn can get?
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3、Which of the following numbers is the largest?
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4、Julie is preparing a speech for her class. Her speech must last between one-half hour and three-quarters of an hour. The ideal rate of speech is 150 words per minute. If Julie speaks at the ideal rate, which of the following number of words would be an appropriate length for her speech?
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5、There are many two-digit multiples of 7, but only two of the multiples have a digit sum of 10. The sum of these two multiples of 7 is
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6、In the number the value of the place occupied by the digit 9 is how many times as great as the value of the place occupied by the digit 3?
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7、The area of the smallest square that will contain a circle of radius 4 is
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8、Walter gets up at 6:30 ., catches the school bus at 7:30 ., has 6 classes that last 50 minutes each, has 30 minutes for lunch, and has 2 hours additional time at school. He takes the bus home and arrives at 4:00 . How many minutes has he spent on the bus?
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9、Three students, with different names, line up single file. What is the probability that they are in alphabetical order from front-to-back?
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10、What fraction of this square region is shaded? Stripes are equal in width, and the figure is drawn to scale.
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11、Let mean the number of whole number divisors of . For example, because 3 has two divisors, 1 and 3. Find the value of
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12、
Find
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13、Three bags of jelly beans contain 26, 28, and 30 beans. The ratios of yellow beans to all beans in each of these bags are , , and , respectively. All three bags of candy are dumped into one bowl. Which of the following is closest to the ratio of yellow jelly beans to all beans in the bowl?
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14、There is a set of five positive integers whose aver