题库 | 考满分，百万出国党的口碑之选。

序号	题目内容
201	What is the difference between the sixth and the fifth terms of the sequence 2,4, 7,... whose $$n^{th}$$ term is $$n + {2}^{n-1}$$?
202	The probability is $$\frac{1}{2}$$ that a certain coin will turn up heads on any given toss. If the coin is to be tossed three times, what is the probability that on at least one of the tosses the coin will turn up tails?
203	Of the final grades received by the students in acertain math course, $$\frac{1}{5}$$ are A's, $$\frac{1}{4}$$ are B's,$$\frac{1}{2}$$ are C's,and the remaining 10 grades are D's. What is the number of students in the course?
204	From the consecutive integers -10 to 10, inclusive, 20 integers are randomly chosen with repetitions allowed. What is the least possible value of the product of the 20 integers?
205	Last Sunday a certain store sold copies of Newspaper A for $1.00 each and copies of Newspaper B for $1.25 each, and the store sold no other newspapers that day. If r percent of the store`s revenues from newspaper sales was from Newspaper A and if p percent of the newspapers that the store sold were copies of newspaper A, which of the following expresses r in terms of p?
206	$${\frac{0.99999999}{1.0001}}-{\frac{0.99999991}{1.0003}}=$$
207	The ratio, by volume, of soap to alcohol to water in a certain solution is 2:50:100. The solution will be altered so that the ratio of soap to alcohol is doubled while the ratio of soap to water is halved. If the altered solution will contain 100 cubic centimeters of alcohol, how many cubic centimeters of water will it contain?
208	A store currently charges the same price for each towel that it sells. If the current price of each towel were to be increased by $1, 10 fewer of the towels could be bought for $120, excluding sales tax. What is the current price of each towel?
209	If n = 4p, where p is a prime number greater than 2, how many different positive even divisors does n have, including n ?
210	In the rectangular coordinate system above, if point R (not shown) lies on the positive y-axis and the area of triangle ORP is 12, what is the y-coordinate of point R ?
211	Car A is 20 miles behind Car B, which is traveling in the same direction along the same route as Car A. Car A is traveling at a constant speed of 58 miles per hour and Car B is traveling at a constant speed of 50 miles per hour. How many hours will it take for Car A to overtake and drive 8 miles ahead of Car B ?
212	For the past n days, the average (arithmetic mean) daily production at a company was 50 units. If today's production of 90 units raises the average to 55 units per day, what is the value of n ?
213	$${(\frac{x+1}{x-1})}^{2}$$If $${x}\neq{0}$$ and $${x}\neq{1}$$, and if x is replaced by $$\frac{1}{x}$$ everywhere in the expression above, then the resulting expression is equivalent to
214	In the figure above, if z = 50, then x + y =
215	In the coordinate system above, which of the following is the equation of line ￡ ?
216	If a two-digit positive integer has its digits reversed, the resulting integer differs from the original by 27. By how much do the two digits differ?
217	The circle with center C shown above is tangent to both axes. If the distance from 0 to C is equal to k, what is the radius of the circle, in terms of k ?
218	In an electric circuit, two resistors with resistances x and y are connected in parallel. In this case, if r is the combined resistance of these two resistors, then the reciprocal of r is equal to the sum of the reciprocals of x and y. What is r in terms of x and y ?
219	Xavier, Yvonne, and Zelda each try independently to solve a problem. If their individual probabilities for success are $$\frac{1}{4}$$, $$\frac{1}{2}$$ and $$\frac{5}{8}$$ respectively, what is the probability that Xavier and Yvonne, but not Zelda, will solve the problem?
220	if $$\frac{1}{x}-\frac{1}{x+1}=\frac{1}{x+4}$$ then x could be

序号

题目内容

201

What is the difference between the sixth and the fifth terms of the sequence 2,4, 7,... whose $$n^{th}$$ term is $$n + {2}^{n-1}$$?

202

The probability is $$\frac{1}{2}$$ that a certain coin will turn up heads on any given toss. If the coin is to be tossed three times, what is the probability that on at least one of the tosses the coin will turn up tails?

203

Of the final grades received by the students in acertain math course, $$\frac{1}{5}$$ are A's, $$\frac{1}{4}$$ are B's,$$\frac{1}{2}$$ are C's,and the remaining 10 grades are D's. What is the number of students in the course?

204

From the consecutive integers -10 to 10, inclusive, 20 integers are randomly chosen with repetitions allowed. What is the least possible value of the product of the 20 integers?

205

Last Sunday a certain store sold copies of Newspaper A for $1.00 each and copies of Newspaper B for $1.25 each, and the store sold no other newspapers that day. If r percent of the store`s revenues from newspaper sales was from Newspaper A and if p percent of the newspapers that the store sold were copies of newspaper A, which of the following expresses r in terms of p?