In the question, they give you the formula for speed...
speed = distance / time
They also give you the distance and the time, so all we have to do is stick them into the equation...
speed = 3 2/3 Km / 1/3 hour
speed = 3 2/3 / 1/3
To divide the fractions, first we need to convert 3 2/3 into an improper fraction
3 2/3 = 11/3
now we multiply 11/3 x the reciprocal of the divisor 1/3. The reciprocal just means flip the numerator and denominator
speed = 11/3 x 3/1
speed = 33/3
speed = 11 Km/hour