Question

A can do a work in 21 days B is 40/ more efficient than A . The number of days required for B finish the same work alone plz ans.....

Answer 1

D)18 hoga brother or ek baar google pr check kr lena

Answer 2

a did work in 21 days so he will do work ina day of 1/21×100=4.76℅

now b is 40℅ more efficient so his work will will be 100=40+x
x=60℅

now the 60℅ of work will be finished in 60/4.76=
12 days answer

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