Work from Days – If A can do a piece of work in n, then A’s 1 day work is 
Days from Work – If A’s 1 day work is
Ratio of work – If A is thrice as good as B, then ration of work done by A and B is 3:1 whereas, ratio of time taken by A and B to complete the work is 1:3.
Formulae:
Tips & Tricks:
Whenever, different men and women are engaged in work, find the ratio between the work done by men and women. Then convert all the ratios in single Units i.e. either men or women.
e.g.
10 Men and 12 Women do a work in 10 Days
and,
8 Men and 4 Women do the same work in 5 Days
then,
(10M + 12W) X 10 = (8M + 4W) x 5
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