Answer:
3/4
Step-by-step explanation:
A: students present
B: students on time
P(all students present and on time) = P(A and B) = 3/10
P(all students present) = P(A) = 2/5
P(A and B) = P(A).P(B|A) where P(B|A) is the probability of everyone being on time given that everyone is present
So P(B|A) = P(A and B) /P(A) = 3/10 ÷ 2/5 = 3/10 * 5/2 = 15/20 which can be reduced to 3/4 by dividing numerator and denominator by 5
You only need to solve one part of the problem, because the second problem is the exact same as the first, so you would do 53 x 6= 318, and 6 x 53 also equals 318
