Correct Answer - Option 4 : 22 hours
Given:
Speed of boat in still water = 16 km/hr
Speed of the stream = 6 km/hr
Distance covered in downstream = 220 km
Formulas Used:
Time = Distance/Speed
S(upstream) = S(boat) - S(stream)
Calculation:
S(upstream) = S(boat) - S(stream)
⇒ S(upstream) = (16 - 6) km/hr
⇒ S(upstream) = 10 km/hr
Time = Distance/Speed
⇒ T = 220/10 hr
⇒ T = 22 hr
∴ The time taken by boat is 22 hours