# General Rules to Solve Time and Work Problems- Download in PDF

Dear Aspirants, Here we have given the General Rules to Solve Time and Work Problems in PDF. Candidates those who are preparing for the Competitive examinations can use this.

Rule 1: Universal Rule
This rule can be used in almost every problem.
If M1 persons can do W1 work in D1 days and M2 persons can do W2 works in D2 days then we can say
M1×D1×W2 = M2×D2×W1
If the persons work T1 and T2 hours per day respectively then the equation gets modified to
M1×D1×T1×W2 = M2×D2×T2×W1
If the persons has efficiency of E1 and E2 respectively then,
M1×D1×T1×E1×W2 = M2×D2×T2×E2×W1

Rule 2:If A can do a piece of work in n days, then the work done by A in one day = 1/n
Rule 3:If A can do a work in D1 days and B can do the same work in D2 days then A and B together can do the same work in    (D1×D2)/(D1+D2) days.
Rule 4:If A is twice as good a workman as B, then A will take half of the time taken by B to complete a piece of work.
Rule 5:If A is thrice as good a workman as B, then A will take one third of the time taken by B to complete a piece of work.
Rule 6:If A and B together can do a piece of work in x days, B and C together can do in y days and C and A together can do in z days, then the same work can be done
By A alone in 2xyz/(xy+yz-zx) days.
By B alone in 2xyz/(yz+zx-xy) days.
By C alone in 2xyz/(zx+xy-yz) days.
By A, B and C together in 2xyz/(yz+zx+xy) days.
Rule 7:If A can do a piece of work in D1 days, B can do in D2 days and C can do in D3 days then they together can do the same work in D1×D2×D3/ (D1×D2+D2×D3+D1×D3) days.
Rule 8:If A and B together can do a piece of work in D1 days and A alone can do it in D2 days, then B alone can do the work in D1×D2/ D2-D1 days.
Rule 9:If the number of men are changed in the ratio of m:n, then the time taken to complete the work will change in the ratio n:m 