Question

Two persons $P$ and $Q$ start at the same time from city $A$ to city $B$, $60$ km away $P$ travels $40$ km/hr slower than $Q$, $Q$ reaches city $B$ and at once turns back meeting $P$, $12$ km from city $B$.What is the speed of $P$?

• A. $8$ km/hr
• B. $12$ km/hr
• C. $16$ km/hr
• D. $20$ km/hr

Answer 1

Answer: (A)

$8$ km/hr

Let the speed of P be x km/hr Speed of Q = (x + 4) km/hr
Distance travelled by Q = (60 + 12) km = 72 km
Distance travelled by P = (60 - 12) km = 48 km
$\Rightarrow \frac{72}{x+4}=\frac{48}{x}\Rightarrow 72x=48x+192\Rightarrow 24x=192=x=\frac{192}{24}=8$