题库 | 考满分，百万出国党的口碑之选。

序号	题目内容
201	A sequence of numbers $${a}_{1}$$, $${a}_{2}$$, $${a}_{3}$$, ... is defined as follows:$${a}_{1}$$ = 3, $${a}_{2}$$ = 5, and every term in the sequence after $${a}_{2}$$ is the product of all terms in the sequence preceding it, e.g., $${a}_{3}$$ = ($${a}_{1}$$)($${a}_{2}$$) and $${a}_{4}$$ =($${a}_{1}$$)($${a}_{2}$$)($${a}_{3}$$). If $${a}_{n}$$ = t and n > 2, what is the value of $${a}_{n+2}$$ in terms of t?
202	Last year the price per share of Stock X increased by k percent and the earnings per share of Stock X increased by m percent, where k is greater than m. By what percent did the ratio of price per share to earnings per share increase, in terms of k and m?
203	Of the 300 subjects who participated in an experiment using virtual-reality therapy to reduce their fear of heights, 40 percent experienced sweaty palms, 30 percent experienced vomiting, and 75 percent experienced dizziness. If all of the subjects experienced at least one of these effects and 35 percent of the subjects experienced exactly two of these effects, how many of the subjects experienced only one of these effects?
204	if $${m}^{-1}=-\frac{1}{3}$$,then $${m}^{-2}$$ is equal to
205	A photography dealer ordered 60 Model X cameras to be sold for $250 each, which represents a 20 percent markup over the dealer`s initial cost for each camera. Of the cameras ordered, 6 were never sold and were returned to the manufacturer for a refund of 50 percent of the dealer's initial cost. What was the dealer's approximate profit or loss as a percent of the dealer`s initial cost for the 60 cameras?
206	Seven pieces of rope have an average (arithmetic mean) length of 68 centimeters and a median length of 84 centimeters. If the length of the longest piece of rope is 14 centimeters more than 4 times the length of the shortest piece of rope, what is the maximum possible length, in centimeters, of the longest piece of rope?
207	What is the difference between the sixth and the fifth terms of the sequence 2,4, 7,... whose $$n^{th}$$ term is $$n + {2}^{n-1}$$?
208	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?
209	The letters D, G, I, I, and T can be used to form 5-letter strings such as DIGIT or DGIIT. Using these letters, how many 5-letter strings can be formed in which the two occurrences of the letter I are separated by least one other letter?
210	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?
211	$${\frac{0.99999999}{1.0001}}-{\frac{0.99999991}{1.0003}}=$$
212	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 ?
213	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 ?
214	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 ?
215	$${(\frac{x+1}{x-1})}^{2}$$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
216	In the figure above, if z = 50, then x + y =
217	In the coordinate system above, which of the following is the equation of line ￡ ?
218	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?
219	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 ?
220	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 ?

序号

题目内容

201

A sequence of numbers $${a}_{1}$$, $${a}_{2}$$, $${a}_{3}$$, ... is defined as follows:$${a}_{1}$$ = 3, $${a}_{2}$$ = 5, and every term in the sequence after $${a}_{2}$$ is the product of all terms in the sequence preceding it, e.g., $${a}_{3}$$ = ($${a}_{1}$$)($${a}_{2}$$) and $${a}_{4}$$ =($${a}_{1}$$)($${a}_{2}$$)($${a}_{3}$$). If $${a}_{n}$$ = t and n > 2, what is the value of $${a}_{n+2}$$ in terms of t?

202

Last year the price per share of Stock X increased by k percent and the earnings per share of Stock X increased by m percent, where k is greater than m. By what percent did the ratio of price per share to earnings per share increase, in terms of k and m?

203

Of the 300 subjects who participated in an experiment using virtual-reality therapy to reduce their fear of heights, 40 percent experienced sweaty palms, 30 percent experienced vomiting, and 75 percent experienced dizziness. If all of the subjects experienced at least one of these effects and 35 percent of the subjects experienced exactly two of these effects, how many of the subjects experienced only one of these effects?

204

if $${m}^{-1}=-\frac{1}{3}$$,then $${m}^{-2}$$ is equal to

205

A photography dealer ordered 60 Model X cameras to be sold for $250 each, which represents a 20 percent markup over the dealer`s initial cost for each camera. Of the cameras ordered, 6 were never sold and were returned to the manufacturer for a refund of 50 percent of the dealer's initial cost. What was the dealer's approximate profit or loss as a percent of the dealer`s initial cost for the 60 cameras?