大家好:
请教大家GRE online practice-1 Q问题:
1. A rectangular game board is composed of identical squares arranged in a
rectangular array of r rows and r+1 columns. The r rows are numbered from 1
through r, and the r+1 columns are numbered from 1 through r+1. If r>10, which
of the following represents the number of squares on the board that neither in
the 4th row nor in the 7th columns? (看不懂题目)
1. r2-r (ANS)
2. r2-1
3. r2
4. r2+1
5. r2+r
* 2表示平方
2. If a<= b<= c<= d<= e<= 110 and the average of a, b, c, d, and e is100,
what is the least possible value of a?
0 20 40 60(ANS) 80
3.How many three-digit positive integers are there such that the three digits
are 3,4, and 8?
3 6(ANS) 9 15 96
本来想说这题是3*4*8=96, 个位数=6, 但题目还是不是很懂!
感谢大家!