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xmagedo
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A box contains 25 red blacks, 100 blue blocks, and 175 yellow blocks. 19 Jul 2010, 03:07
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B
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A box contains 25 red blacks, 100 blue blocks, and 175 yellow blocks. What is the probability that a block picked at random from the box will be red ?

A. 1/25
B. 1/12
C. 1/7
D. 1/5
E. 1/3
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B
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A box contains 25 red blacks, 100 blue blocks, and 175 yellow blocks. 19 Jul 2010, 03:40
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There are 25 reds out of 300 blocks.

25/300 = 1/12 (B)
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A box contains 25 red blacks, 100 blue blocks, and 175 yellow blocks. 19 Jul 2010, 04:33
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You're right. It would be B.
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A box contains 25 red blacks, 100 blue blocks, and 175 yellow blocks. 07 Dec 2017, 14:50
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Hi All,

This question is an example of a fairly straight-forward probability question.

Probability = (# of ways that give us what we "want")/(Total # of ways possible).

Here, we have a total of 25+100+175 = 300 blocks and 25 of those blocks are red. Thus, the probability of randomly pulling one red block from that group is...

25/300 = 1/12

Final Answer:
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B


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A box contains 25 red blacks, 100 blue blocks, and 175 yellow blocks. 05 Feb 2020, 05:53
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xmagedo
A box contains 25 red blacks, 100 blue blocks, and 175 yellow blocks. What is the probability that a block picked at random from the box will be red ?

A. 1/25
B. 1/12
C. 1/7
D. 1/5
E. 1/3
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The box contains 25 + 100 + 175 = 300 blocks. Since there are 25 red blocks, the probability of picking one red block out of the box is 25/300 = 1/12.

Answer: B
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A box contains 25 red blacks, 100 blue blocks, and 175 yellow blocks. 01 Dec 2020, 07:58
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xmagedo
A box contains 25 red blocks, 100 blue blocks, and 175 yellow blocks. What is the probability that a block picked at random from the box will be red ?

A. 1/25
B. 1/12
C. 1/7
D. 1/5
E. 1/3
Show more

There are 25 red blocks
There are 300 blocks in total (25 + 100 +175 = 300)

P(block is red) = (number of ways to select a red block)/(total number of outcomes)
= 25/300
= 1/12

Answer: B

Cheers,
Brent
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A box contains 25 red blacks, 100 blue blocks, and 175 yellow blocks. 25 Feb 2026, 20:50
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