
Work from Days:
If A can do a piece of work in n days, then A's 1 day's work = 
1 
. 
n 

Days from Work:
If A's 1 day's work = 
1 
, 
then A can finish the work in n days. 
n 

Ratio:
If A is thrice as good a workman as B, then:
Ratio of work done by A and B = 3 : 1.
Ratio of times taken by A and B to finish a work = 1 : 3.
