数学求解题过程，帮翻译一下题，谢谢~~~

sonic316

1.Each of the integers from 0-9, inclusive, is written on a separate slip of blank paper and the ten slips are dropped into a hat. If the slips are then drawn one at a time without replacement, how many must be drawn to ensure that the numbers on two of the slips drawn will have a sum of 10?

A.3
B.4
C.5
D.6
E.7



2.Set S consists of n distinct positive integers, none of which is greater than 12. What is the greatest possible value of n if no two integers in S have a common factor greater than 1?

A.4
B.5
C.6
D.7
E.11


3.This year H  will save a certain amount of his income, and he will spend the rest. Next year H will have no income,but for each dollar that he saves this year, he will have 1+r dollars available to spend. In TERMS OF R, What fraction of his income should H save this year so that next year the amount he was available to spend will be equal to half the amount that he spends this year?

A.1/r+2
B.1/2r+2
C.1/3r+2
D.1/r+3
E.1/2r+3

4.Car X and Y were traveling together on a straight road at a constant speed of 55 miles per houre when car X stopped for 5 minytes. If car Y continued to travel at 55 miles per hour, how many minutes from time that car X traveling at 60 miles per hour to catch up with car Y? (Assume that the time for car X slow down and speed up was negligble.)


A.5
B.30
C.45
D.55
E.60



5.In a certain contest, F must select any 3 of 5 different gifts offered by the sponsor. From how many different combinations of 3 gifts can F make his selection?

A.10
B.15
C.20
D.30
E.60



6.If a car averaged 22.5 miles per gallon of gasoline, approximately how many kilometers per liter of gasoline did the car average?(1mile =1.6 kilometers and 1 gallon= 3.8 liters, both rounded to the nearest tenth.)

A.3.7
B.9.5
C.31.4
D.53.4
E.136.8



7.(1/100-2/1000)/(1/1000-2/10000)=?


A.1/10
B.1/8
C.1
D.8
E.10

sdcar2010

Well, truth hurts.

sonic316

The rest are too boring to calculate even for a high schooler.

-- by 会员 sdcar2010 (2011/3/1 12:01:48)

本人英语不太好，可能有时候翻译不准，而且我想找找有没有快速简洁的方法来解这些题，如果你觉得无聊的话，就不要看了

sdcar2010

The rest are too boring to calculate even for a high schooler.

sdcar2010

2.Set S consists of n distinct positive integers, none of which is greater than 12. What is the greatest possible value of n if no two integers in S have a common factor greater than 1?

A.4
B.5
C.6
D.7
E.11

It just ask you for the numbers of prime number smaller than 12, then plus 1.

11, 7,5,3,2,1. CCCCCCCCCCCCC

sdcar2010

1.Each of the integers from 0-9, inclusive, is written on a separate slip of blank paper and the ten slips are dropped into a hat. If the slips are then drawn one at a time without replacement, how many must be drawn to ensure that the numbers on two of the slips drawn will have a sum of 10?

A.3
B.4
C.5
D.6
E.7

The worst case scenario: 0, 9, 8, 7,6, 5. Basically you pick 0 and 5, then pick one from the other 4 pairs.   So choose E.