Let y be the number of yellow marbles

There are 11+7+y=18+y total marbles.

y/(18+y)=1/4.

4y=18+y

3y=18

y=6

There are 6 yellow marbles.

# Answer

6
Question:
In the jar, there are 7 blue marbles, 11 red marbles, and some yellow marbles. If the chance of randomly picking a yellow marble is 1/4, how many yellow marbles are there?
Answer:
Let's think step by step.

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6
In the jar, there are 7 blue marbles, 11 red marbles, and some yellow marbles. If the chance of randomly picking a yellow marble is 1/4, how many yellow marbles are there?
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