Given a grid with 15 sections, determine how many sections in the grid need to be shaded so the probability of a point chosen at random in the shaded area is exactly 0.8. explain your reasoning

12

Step-by-step explanation:

0.8 is equal to 80%

you need to figure out 80% of 15

100% = 15

10% = 1.5

(x8)

80% = 12

you would need to shade 12 out of 15 boxes which gives 0.8 chance of picking a shaded one

Sample The number of squares that are shaded divided by 15 must equal 0.8, so the number of squares must be 0.8(15), which equals 12. The fraction 12/15 reduces to 4/5 which is equal to 8/10.

Step-by-step explanation:

The sample answer on edge

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