The probability of selecting red marble is 0.444.
Probability is calculated using the formula :
Probability = number of favourable outcomes ÷ total number of outcomes
Number of favourable outcomes = number of red marbles in box
Number of favourable outcomes = 8
Total number of outcomes = total number of marbles
Total number of outcomes = 8 + 4 + 6
Total number of outcomes = 18
Keep the values in formula of probability to find the probability of selecting red marble
Probability = 8 ÷ 18
Performing Division by 2
Probability = 4/9
Representing in decimal round to three decimal places = 0.444
Hence, the probability of selecting red marble is 0.444.
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