On a river, Q is the mid-point b/w two points P and R on the same bank of the river. A boat can go from P to Q and back in 12 hours, and form P to R in 16 hours 40 min. How long would it take to go from R to P?
Answer & explanation
Correct answer: option 4
P_________ Q___________ R
↓
P to Q
Q to P = 12 hrs ---- (i)
This is the same time to go from Q to R and bacl, since distance is same = 12
Time to go from P to Q = Q to R
total = 16 hr 40 min
time from P to Q = 8 hr 20 min
From eq (i)
time taken from Q to P = 12 hr - 8 hr 20 min
= 3 hr 40 min
Time taken to go from R to P = 2 x (3 hr 40 min)
= 7 hr 20 min or 7\(\frac{1}{3}\) hrs