Question 1203168
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Given that 3/8 of the marbles are red, let 8x be the total number of marbles and 3x be the number of red marbles.  Then the number of marbles of other colors is 8x-3x = 5x.<br>
70% of the remaining marbles are yellow. 70% of 5x is 0.7(5x) = 3.5x.<br>
The total number of red and yellow marbles is 3x+3.5x = 6.5x; the total number of marbles is 8x.  So the number of green marbles is 8x-6.5x = 1.5x.<br>
The number of green marbles is 12:<br>
1.5x = 12
x = 12/1.5 = 8<br>
ANSWER: The total number of marbles in the bag is 8x = 64<br>