GWD 31 求教Q2，Q25，Q31

norlanzhang

Q2:
The fuction f is defined for each positive three-digit integer n by f(n)=(2^x)(3^y)(5^z), where x, y, z are the hundreds, tens, units digits of n, respectively. If m and v are three-digit posotive integers such that f(m)=9f(v), then m-v=?
A.8
B.9
C.18
D.20
E.80

Q25:
For a certain race, 3 teams were allowed to enter 3 members each. A team earned 6-n points whenever one of its members finished in nth place, where 1≤n≤5. There were no ties, disqualifications, or withdrawals. If no team earned more than 6 points, what is the least possible score a team could have earned?
A.0
B.1
C.2
D.3
E.4

Q31:
There are 5 cars to be displayed in 5 parking spaces with all the cars facing the same direction. Of the 5 cars, 3 are red, 1is blue, and 1 is yellow. If the cars are identical except for color, how many different display arrangements of the 5 cars are possile?
A.20
B.25
C.40
D.60
E.125

maggie02

Q31:   是P5  2   答案A    五个位子选2个给蓝黄，其他3个放进去就是了

maggie02

Q25    一共是15分 有2个6 最后一个最小是3.

maggie02

Q2    D.20   十位数相差2  .   答案对不？我没看答案

ghmf334

Q2都没看懂什么意思……我菜鸟……