Question

The diagram shows the contents of a jar of marbles. You select two marbles at random. One marble is drawn and not replaced. Then a second marble is drawn. What is the probability of selecting a red marble and then another red marble?
A) 3/64
B) 1)4
C) 1/20
D) 1/30
( there are 7 blue marbles, 5 green marbles, and 4 red marbles)

Answer 1

Since these are dependant, it is 4/16 times 3/15 since you took one out and did not replace. so C, 1/20

Answer 2

Answer:

Option C is the answer.

Step-by-step explanation:

There are some marbles in a jar

Blue -  7  marbles

Green -  5 marbles

Red  - 4 marbles

Total = 16 marbles

You selected two marbles at random without replacing any.

So the probability that first marble drawn is red = $\frac{4}{16}$

Now without replacing you selected another marble, So the probability that second marble is red = $\frac{3}{15}$

$P_{1}$ = $\frac{4}{16}$

$P_{2}$ =  $\frac{3}{15}$

P = $\frac{4}{16}$ × $\frac{3}{15}$ = $\frac{1}{20}$

The probability of selecting a red marble and then another red marble is

$\frac{1}{20}$.

Option C is the answer.