If 30 labourers working 7 hours a day can finish a piece of work in 18

1.	If 30 labourers working 7 hours a day can finish a piece of work in 18 days, how many labourers working6 hours a day can finish it in 30 days?
Answer» As 30 labours complete work in 187 hours=126 hours let x labours nedded to complete work in =630=180hours This is case of inverse variation, So, 30126=x180 x=30*126/180=21 labours

If 30 labourers working 7 hours a day can finish a piece of work in 18 days, how many labourers working6 hours a day can finish it in 30 days?

Answer»

As 30 labours complete work in 18*7 hours=126 hours

let x labours nedded to complete work in =6*30=180hours

This is case of inverse variation,

So, 30*126=x*180

x=30*126/180=21 labours