Question

1. 45% of the students passed their latest mathematics test. 30% of the students were present during the lectures, and 18% passed their test and were present. What percentage of those who passed their test also were present in class?

2. You throw a two dice at once. X1 defines the number of pips (dots) on the upper surface of die 1 and X2 defines the number of pips on the upper surface of die 2. Calculate the probability of:
(a) X1 = 1 and X2 = 2
(b) X1 + X2 is odd and X1*X2 is even
(c) X1/X2 is at least 1, provided X2 is a prime number (meaning X2 = 2, 3 or 5).

Answer 1