Answer:
9 questions
Explanation:
I dunno if this is the correct answer but if you divide 1 and 1/2 hours by 1/6 hours that it takes him to answer each question then it would be 9 questions
1/6 hour = 10 minutes
1.5 hours = 90 minute
Therefore Isaac can solve 9 questions in 1.5 hours.
7.8m questions
10.5m answers