Question

The table below shows the number of marbles of different colors in a bag:

Marble Experiment

Color of
Marbles Number of
Marbles
Red
1
White
5
Black
10


Ursula draws a marble from the bag randomly without looking. She then draws another marble from the bag without replacing the first one. Which expression shows the probability of drawing black marbles in both the trials?
10 over 16 added to 9 over 16
10 over 16 added to 9 over 15
10 over 16 multiplied by 9 over 16
10 over 16 multiplied by 9 over 15

Answer 1

First off, the probability of drawing a black marble at the start is equivalent to what?
Considering P = number of black balls/total number of balls

Answer 2

1)10over16

Answer 3

2)9 over15

Answer 4

i think its d

Answer 5

yes

Answer 6

That's correct! Because our answer is going to be (number of black balls/total number of balls) * (number of black balls - 1/ total number of balls -1) *-1 because we drew one, right?*

Answer 7

Leslie rolls two fair number cubes numbered from 1 to 6. She first defines the sample space, as shown below:

(1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6)
(2, 1), (2, 2), (2, 3), (2, 4), (2, 5), (2, 6)
(3, 1), (3, 2), (3, 3), (3, 4), (3, 5), (3, 6)
(4, 1), (4, 2), (4, 3), (4, 4), (4, 5), (4, 6)
(5, 1), (5, 2), (5, 3), (5, 4), (5, 5), (5, 6)
(6, 1), (6, 2), (6, 3), (6, 4), (6, 5), (6, 6)

Based on the sample space, what is the probability of getting a total of 11?

2 over 36
3 over 36
4 over 36
5 over 36