EfficiencyofP:Q=2:1</p><pstyle="color:rgb(0,0,0);margin−top:2px;margin−bottom:2px"data−pxy="true">Q takes 12 days to complete the work
Total work be$=12\times1=12$
Both of them working together efficiecncy be 3
$$Time required to complete the work $=\frac{12}{3}$
$=4days$