A family discount card offers deals for the cinema. The cost of an adult ticket is £10. A child's ticket is £6. (a) How much will it cost to buy 2 adult tickets and 3 children's tickets? (b) The cost of a family discount card is £40 per year. How many times in the same year would 2 adults and 3 children need to go before you start to save money on the cost of the card?

probability for j is 1/4

while

a is 1/6

85.560%

step-by-step explanation:

conditional probability is defined as:

p(a|b) = p(a∩b) / p(b)

in other words, the probability that a occurs, given that b has occurred = the probability that both a and b occur / the probability that b occurs.

in this example:

p(turns 64 | turns 44) = p(turns 64 & turns 44) / p(turns 44).

if someone turns 64, they must have already turned 44, so:

p(turns 64 | turns 44) = p(turns 64) / p(turns 44)

on page 42, we see that of the original 100,000, 94944 turn 44, and 81234 turn 64.   therefore:

p(turns 64 | turns 44) = 81234 / 94944

p(turns 64 | turns 44) = 0.85560

66% of the price that was mark on the bottom