A bag of marbles has twice as many blue marbles as green marbles, and the bag has at least 54 marbles in it. At least how many green marbles does it have in it?

My! You have a major identity problem, John/Brian/Sam/Nancy/Jessica/Mark/Kaela!

Please use only one name for your posts.

1/3 of the marbles are green.

So, 1/3 of at least 54 are green.
How many is that?

To find out the minimum number of green marbles in the bag, we can set up a simple equation based on the given information.

Let's assume the number of green marbles in the bag is "x". According to the problem, the bag has twice as many blue marbles as green marbles. Therefore, the number of blue marbles can be represented as "2x".

Since the bag has at least 54 marbles, the total number of marbles is greater than or equal to 54. Now, we can set up an inequality to represent this information:

x + 2x ≥ 54

Combining like terms, we get:

3x ≥ 54

Now, divide both sides of the inequality by 3 to solve for x:

x ≥ 54/3

x ≥ 18

Therefore, the minimum number of green marbles in the bag is 18.