There is an urn containing 10 marbles numbered 1 to 10. We sample 4 marbles without replacement. What is the probability that our sample contains the marbles labeled 1 and 2

Step-by-step explanation:

The easiest way to do this is to assume you don't get a 1 or 2. You make your first draw from 8.

8 * 7 * 6 * 5 = 1680

The total number of ways of drawing 4 marbles is

10*9 * 8 * 7 = 5040

P(`(1 or 2) ) = 1680 / 5040 = 0.33333

The probability of getting a 1 or 2 in 4 throws = 1 - 0.3333 = 0.66667

check the picture below.

well, the angle at the vertex d is clearly not a right-angle, let's check for the one at the vertex f which does look like,   however if it's indeed, that means ef is perpendicular to df, in which case their slopes will be negative reciprocal of each other.

so the negative reciprocal of the slope of ef is 1, however the slope of df is not 1, is 1/2, so nope, they're not perpendicular lines.

answer: 1) twenty-seven times y

              2) twenty-seven multiplied by y