MHB There are z red marbles. How many green marbles are there?

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In the discussion about marbles, the relationship between red, blue, and green marbles is established, with blue marbles being twice the number of red marbles and green marbles having three more than blue. For z red marbles, the number of green marbles is calculated as 2z + 3. When given that there are 19 green marbles, the calculation for red marbles leads to 2 * 19 + 3, resulting in 41. The importance of correctly interpreting "more" in the context of the problem is emphasized. The conversation highlights the need for clarity in mathematical notation and relationships.
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In a container, there are some blue, red and green marbles. There are twice as many blue marbles as red marbles, and there are 3 more green marbles than blue marbles.

a) There are z red marbles. How many green marbles are there?

my answer: z + 2z + 6z = 9zb) There are 19 green marbles in the container. Find the number of red marbles.

my answer 19/3 = 6.3/2 = 3.2 red marbles.
 
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Johnx said:
In a container, there are some blue, red and green marbles. There are twice as many blue marbles as red marbles, and there are 3 more green marbles than blue marbles.

a) There are z red marbles. How many green marbles are there?

my answer: z + 2z + 6z = 9zb) There are 19 green marbles in the container. Find the number of red marbles.

my answer 19/3 = 6.3/2 = 3.2 red marbles.
I like my notation better. Sorry.

Say we have r red marbles. Then we have b = 2r blue marbles. Now, be careful. "there are 3 more green marbles than blue marbles." That means we have g = b + 3 green marbles, not 3 times b. So g = b + 3 = 2r + 3. (or 2z + 3.) Notice that this gives you an integer number of red marbles.

Can you finish it from here?

-Dan
 
topsquark said:
I like my notation better. Sorry.

Say we have r red marbles. Then we have b = 2r blue marbles. Now, be careful. "there are 3 more green marbles than blue marbles." That means we have g = b + 3 green marbles, not 3 times b. So g = b + 3 = 2r + 3. (or 2z + 3.) Notice that this gives you an integer number of red marbles.

Can you finish it from here?

-Dan

Your notations are great. I red it incorrect when it comes to the "more" part.

a ) 2z + 3

b) 2* 19 + 3 = 41
 
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