Boris is taking a quiz for an online class. for the quiz, the  system randomly assigns  2  high-difficulty questions,  7  moderate-difficulty questions, and  6  low-difficulty questions. what is the probability that boris is  assigned a moderate-difficulty question first?
give your answer as a fraction.

Mr and mrs smith buy tickets for themselves and their four children. the cost of an adult ticket is ? 6 more than the adult ticket. the total cost of the six tickets is ? 40.50 work out the cost of an adult ticket. in your working let c be the cost of the child ticket and a be the cost of the adult ticket.

Identify the number 127 as a rational or irrational. explain

What is the interquartile range of this data set? 2, 5, 9, 11, 18, 30, 42, 48, 55, 73, 81