Multiple choice

A man can row the boat with the stream at the speed of 11 km/hour and against the stream at the speed of 8 km/hour, then the speed of the stream is

  1. 3 km/hour

  2. 9.5 km/hour

  3. 1.5 km/hour

  4. 6 km/hour

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let v be the speed of the boat and s be the speed of the stream. We have v + s = 11 and v - s = 8. Subtracting the two equations gives 2s = 3, so s = 1.5 km/hour.

AI explanation

The speed of the stream is found using the formula (downstream speed minus upstream speed) divided by 2. Substituting the given values, we calculate (11 minus 8) divided by 2. This equals 3 divided by 2, giving a speed of 1.5 km/hour.