A = {2, 3, 4, 5}
B= {4, 5, 6, 7, 8}
Two integers will be randomly selected from the sets above, one integer from set A and one integer from set B. WHat is the probability that the sum of the two integers will equal 9?
A. 0.15
B. 0.20
C. 0.25
D. 0.30
E. 0.33
Answer is B
Can someone please tell me how to approach questions such as this? Thanks so much!!
What is the probability that the sum will equal 9??
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- Anurag@Gurome
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There are total 20 ways to sum.gmatpup wrote:A = {2, 3, 4, 5}
B= {4, 5, 6, 7, 8}
Two integers will be randomly selected from the sets above, one integer from set A and one integer from set B. WHat is the probability that the sum of the two integers will equal 9?
A. 0.15
B. 0.20
C. 0.25
D. 0.30
E. 0.33
Answer is B
Can someone please tell me how to approach questions such as this? Thanks so much!!
4 of the sums equals 9.
so, the required probability = 4/20 = 1/5 = .20
The correct answer is B.
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Anurag@Gurome wrote:No. of ways of selecting one number from set A = 4C1 = 4gmatpup wrote:A = {2, 3, 4, 5}
B= {4, 5, 6, 7, 8}
Two integers will be randomly selected from the sets above, one integer from set A and one integer from set B. WHat is the probability that the sum of the two integers will equal 9?
A. 0.15
B. 0.20
C. 0.25
D. 0.30
E. 0.33
Answer is B
Can someone please tell me how to approach questions such as this? Thanks so much!!
No. of ways of selecting one number from set B = 5C1 = 5
Total Ways = 4 * 5 = 20
There are 4 ways in which the sum is 9
1) 2(from A) + 7(from B) = 9
2) 3(from A) + 6(from B) = 9
3) 4(from A) + 5(from B) = 9
4) 5(from A) + 4(from B) = 9
Therefore, required probabiity = 4/20 = 0.2
IMO: B
- tuanquang269
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4 x 5 = 20 ways to choose couple of number each from set A and B
There are 4 couple have sum of 9 include: (2,7) (3,6) (4,5) (5,4)
Probability = 4/20 = 20%
There are 4 couple have sum of 9 include: (2,7) (3,6) (4,5) (5,4)
Probability = 4/20 = 20%
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Total events = 4 * 5= 20gmatpup wrote:A = {2, 3, 4, 5}
B= {4, 5, 6, 7, 8}
Two integers will be randomly selected from the sets above, one integer from set A and one integer from set B. WHat is the probability that the sum of the two integers will equal 9?
A. 0.15
B. 0.20
C. 0.25
D. 0.30
E. 0.33
Answer is B
Can someone please tell me how to approach questions such as this? Thanks so much!!
favorable events = 4 (2+7), (5+4), (4+5), (3+6)
probability = 4/20 = 0.2 (B)
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To make it even more simpler:
Each number in set A can match exactly one number in set B to equal 9.
So if you choose any number from set A, the probability that you choose the right number from set B is 1/5, because only one number out of the 5 will be the right match to equal 9. Therefore the answer is .20.
Each number in set A can match exactly one number in set B to equal 9.
So if you choose any number from set A, the probability that you choose the right number from set B is 1/5, because only one number out of the 5 will be the right match to equal 9. Therefore the answer is .20.
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Let's first determine the total number of outcomes. We have 4 numbers in set A, and 5 in set B, and since we are selecting 1 number from each set, the total number of outcomes is 4 x 5 = 20.gmatpup wrote:A = {2, 3, 4, 5}
B= {4, 5, 6, 7, 8}
Two integers will be randomly selected from the sets above, one integer from set A and one integer from set B. WHat is the probability that the sum of the two integers will equal 9?
A. 0.15
B. 0.20
C. 0.25
D. 0.30
E. 0.33
For our favorable outcomes, we need to determine the number of ways we can get a number from set A and a number from set B to sum to 9. We are selecting from the following two sets:
A = {2, 3, 4, 5}
B = {4, 5, 6, 7, 8}
We will denote the first number as from set A and the second from set B. Here are the pairings that yield a sum of 9:
2,7
3,6
4,5
5,4
We see that there are 4 favorable outcomes. Thus, the probability is 4/20 = 1/5 = 0.2.
Answer: B
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