can real time in benchmark.rb be less than the other other ones?

This is my benchmark.rb开发者_运维问答 output. Is it not weird that real time is less than ther system and total time? or is it okay to have it? I am new to ruby, please forgive me if I sound stupid. Thanks!

user     system      total     real
1.050000   0.000000   1.050000 (0.503462)
1.533333   0.016667   1.550000 (0.735473)
1.500000   0.016667   1.516667 (0.711239)   

My guess is that you ran this on a dual core machine, or at least a multiple core, and it ran two threads.