gistfile1.rb

# randomly generate 0 or 1 ... you should get 1 about 10% of the time, 0 about 90% of the time
 $ irb
>> rand
=> 0.534835738078545
>> rand
=> 0.334280092272696
>> rand * 10
=> 2.22911939494193
>> ( rand * 10 ).to_i
=> 0
>> 15.times { puts ( rand * 10 ).to_i }
4
5
4
7
2
5
4
7
0
0
8
9
5
2
9
=> 15
>> puts "it randomly generates a number from 0 to 9 ..."
it randomly generates a number from 0 to 9 ...
=> nil
>> 15.times { num = ( rand * 10 ).to_i; num = 0 unless num == 1; puts num }
0
0
1
0
0
0
0
0
0
0
0
1
1
0
0
=> 15