新东方GRE数学教程有些题我弄不太明白,希望高人指点!
1.Each person at a party shook hands exactly once with each of the other people at the party.There was a total of 21 handshakes exchanged at the party.
The number of people at the party 8
2.Ms.Smith got an 8 percent cost-of-living raise of $20 per week.
Ms.Smith's new weekly salary $260
3 1<n<5; n is an integer
The sum of the first n odd integers
that are greater than zero n*n-1
4 x and y are numbers on the number line.
x y
5.The area of a tablecloth that The area of a tablecloth that
overhangs a square tabletop by overhangs a rectangular tabletop
3 inches on all sides by 2 inches on all sides
6. RS is a diameter of a circle.
The ratio of the length of diameter 2/3
RS to the length of semicircular arc RS
7.A certain car gets 24 miles per gallon of gasoline for city driving,which is 60 percent
of the number of miles pe gallon of gasoline the car gets for high-way driving.
The number of gallons of gasoline The number of gallons of gasoline
used to drive this ear 30 miles used to drive this car 45 miles
in the city on the highway
8.On a turntable,a record of radius 6 inches is rotating at the rate of 45
revolutions per minute.
The number of inches traveled The number of inches traveled
per minute by a point on the per minute by a point on the
circumference of the record record 5 inches fromthe center of
the record
9.In an election each voter voted for one of two candidates,X and Y.The number of votes that
Candidate X received was 1/3 more than the number of votes that Candidate Y received.
The fraction of the total vote that
Candidate X received 4/7
10 Section 19 的 33题,有个符号实在是弄不上去呀!
11.A spraying machine uses 6 full 5-gallon buckets of fungicide every 20 minutes.
The number of gallons of funigicide
the machine uses during 8 hours 720
of spraying
12. k is a positive integer.
1/2k (k是次幂) (1/3k)+(1/3k)(k是次幂)
13.The charge to transport a van consists of a $23 fixed charge and $2 for each foot of the van's length in excess of 18 feet.The length of pat's van is n feet,where n is integer greater than 18.
The number of dollars charged to 2n-13
transport Pat's van