Question

A car P leaves City C at 7 am and reaches City D at 11 am. Another car Q leaves City D at 9 am and reaches City C at 12:30 pm. At what time do the 2 cars cross one another?

• A. 9:36 AM
• B. 10:36 AM
• C. 9:46 AM
• D. 9:26 AM
• E. 9:56 AM

Answer 1

The correct option is E

9:56 AM

Let the distance between the cities be `x'

They meet after y hr after 9 am

P covers x in 4 hr

Q covers x in $\frac{7}{2}$ hr

Speed of P = $\frac{x}{4}$

Speed of Q = $\frac{2x}{7}$

Distance covered by P in y+2 hr + Distance covered by Q iny hr is x

$\frac{x(y+2)}{4}+\frac{2xy}{7}=x$

y = $\frac{14}{15}$ hr or 56 min