The school is installing whiteboards in 5 classrooms. Whiteboards, including their borders, are 6 feet wide by 10 feet long. The borders, which are 0.5 ft wide, will not be varnished. The whiteboards can be varnished to resist stains for 40
cents per square foot or can be varnished to avoid glare from ceiling lights for 25 cents per square foot. If each room
gets one whiteboard, how much more expensive will it be to varnish the whiteboards for stains than to varnish
them for glare?

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

umm im not really sure because i never had to do this

step-by-step explanation: