marbles numbered from 1 to 12 are put in a bag. if marbles are not put back into the bag after being drawn, what is the probability of drawing two prime numbers in a row?

Step-by-step explanation:

Given

Marbles = 12

Selection without replacement

Required

Determine the probability of selecting 2 primes

Between 1 and 12, the prime digits is 4, and they are: 3, 5, 7 and 11

So, when the first marble is picked, the probability that it will be prime is:

Now there are 3 primes left and 11 marbles in total. So, the probability of selecting another prime is:

The required probability is:

it is b)

hope this : )

step-by-step explanation:

{x = -1/2 ,   y = -1

step-by-step explanation:

solve the following system:

{2 x + y = -2

{10 x - 3 y = -2

in the first equation, look to solve for y:

{2 x + y = -2

{10 x - 3 y = -2

subtract 2 x from both sides:

{y = -2 x - 2

{10 x - 3 y = -2

substitute y = -2 x - 2 into the second equation:

{y = -2 x - 2

{10 x - 3 (-2 x - 2) = -2

10 x - 3 (-2 x - 2) = (6 x + 6) + 10 x = 16 x + 6:

{y = -2 x - 2

{16 x + 6 = -2

in the second equation, look to solve for x:

{y = -2 x - 2

{16 x + 6 = -2

subtract 6 from both sides:

{y = -2 x - 2

{16 x = -8

divide both sides by 16:

{y = -2 x - 2

{x = -1/2

substitute x = -1/2 into the first equation:

{y = -1

{x = -1/2

collect results in alphabetical order:

answer:   {x = -1/2 ,   y = -1