Question 481138
The total population of the blocks in the bucket is the sum of the numbers of blocks of each color.  In other words, the total population is:
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3 yellow + 10 blue + 6 green + 8 red + 3 purple = 30 blocks
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The 8 red blocks represent the number of chances to pick a red block from the total. Therefore, if Sam cannot see the color of the blocks, in one pick he has an 8 in 30 chance of drawing a red block from the 30 possible choices.
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That is the answer to this problem.  The probability of selecting a red block is 8 in 30. It may also be expressed in fractional form as:
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{{{8/30}}}
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and because the both the numerator and denominator are divisible by 2, this fraction can be reduced to the equivalent form of:
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{{{4/15}}}
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This means that Sam has a 4 in 15 chance of drawing a red block.
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And in still another way of expressing this, by dividing the denominators of these two fractions into their respective numerators you can change the fractions {{{8/30}}} and {{{4/15}}} to their common decimal form of 0.266667. Then you can say that the probability of drawing a red block is 0.266667. You can also convert this to percent by moving the decimal point two places to the right so you can say that there is a 26.6667% probability of drawing a red block in one one random pick from the 30 blocks.
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Hope this helps you to understand the problem.
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