SSC GD Constable 6 Feb 2025 Shift 1 Paper

Ravi completes $1∕4$ work in 15 days ⇒ Total time $=15\times 4=60$ days
Chavi completes $1∕3$ work in 18 days ⇒ Total time $=18\times 3=54$ days
Dhani completes $1∕2$ work in 24 days ⇒ Total time $=24\times 2=48$ days
Work rate of each person:
Ravi's rate $=1∕60$ work/day
Chavi's rate $=1∕54$ work $∕$ day
Dhani's rate $=1∕48$ work $∕$ day
Combined rate of all three:
Combined rate $=1∕60+1∕54+1∕48$
LCM of 60,54, and $48=2160$
$1∕60=36∕2160$
$1∕54=40∕2160$
$1∕48=45∕2160$
Combined rate $=\left(36+40+45\right)∕2160=121∕2160$ work $∕$ day
Time to complete $3∕4$ of the work:

$\Rightarrow \left(3∕4\right)\times \left(2160∕121\right)$
$=1620∕121$
Final Answer: $13\frac{47}{121}$ days