In jar A there are 3 white balls and 2 green ones, in jar B there is one white ball and three green ones. A jar is a randomly picked, what is the probability of picking up a white ball out of jar A?
A. 2/5.
B. 3/5.
C. 3/10.
D. 3/4
E. 2/3.
The OA is C.
I'm really confused with this PS question. Please, can any expert assist me with it? Thanks in advanced.
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In jar A there are 3 white balls and 2 green ones...
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BTGmoderatorLU
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Generally:LUANDATO wrote:In jar A there are 3 white balls and 2 green ones, in jar B there is one white ball and three green ones. A jar is a randomly picked, what is the probability of picking up a white ball out of jar A?
A. 2/5.
B. 3/5.
C. 3/10.
D. 3/4
E. 2/3.
AND means MULTIPLY.
OR means ADD.
P(picking Jar A) = 1/2. (Of the 2 jars, one is A.)
P(selecting a white marble from A) = 3/5. (Of the 5 marbles in A, 3 are white.)
Since we want to pick Jar A and select a white marble from A, we MULTIPLY the probabilities:
1/2 * 3/5 = 3/10.
The correct answer is C.
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Hi LUANDATO,In jar A there are 3 white balls and 2 green ones, in jar B there is one white ball and three green ones. A jar is a randomly picked, what is the probability of picking up a white ball out of jar A?
A. 2/5.
B. 3/5.
C. 3/10.
D. 3/4
E. 2/3.
The OA is C.
Let's take a look at your question.
There are two jars A and B.
Jar A has 3 white balls and 2 green ones.
Jar B has one white ball and three green ones
P(Picking up a white ball out of jar A) = P(selecting Jar A) * P(Picking white ball from Jar A)
$$=\frac{1}{2}\times\frac{3}{5}$$
$$=\frac{3}{10}$$
Therefore, Option C is correct.
Hope it helps.
I am available if you'd like any follow up.
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The probability of selecting jar A is 1/2.BTGmoderatorLU wrote:In jar A there are 3 white balls and 2 green ones, in jar B there is one white ball and three green ones. A jar is a randomly picked, what is the probability of picking up a white ball out of jar A?
A. 2/5.
B. 3/5.
C. 3/10.
D. 3/4
E. 2/3.
The OA is C.
I'm really confused with this PS question. Please, can any expert assist me with it? Thanks in advanced.
The probability of selecting a white ball from jar A is 3/5.
Thus, the overall probability is 1/2 x 3/5 = 3/10.
Answer: C
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