- Ait does not state how many of the 9,300 riders have since begun to wear a helmet
- Bit arrives at its total by adding three counts of attendance that may each hold the same rider, a rider who listened at a petrol pump and again at the transport office being counted twice over
- Cit does not say how many talks were given at the petrol pumps and how many at the colleges
- Dit assumes that every rider who attended a talk stayed until the talk was finished
Step-by-Step Solution
The three figures count occasions of listening and the conclusion counts riders, and the two part company the moment one rider listens twice. Since the same young men fill the petrol pumps, the colleges and the queue at the transport office, the overlap is not a remote possibility but the likely case, and 9,300 may stand for four or five thousand people. The first option raises a real question but a different one — the cell claims to have reached riders, not to have converted them — and the sum would be just as faulty if every listener had bought a helmet the same afternoon. How the talks were distributed between the three kinds of place would not tell us which listeners were the same. And whether listeners stayed to the end concerns the quality of each attendance rather than the double counting of persons.
Answer: B) it arrives at its total by adding three counts of attendance that may each hold the same rider, a rider who listened at a petrol pump and again at the transport office being counted twice over