Math problem.......? *sigh*

Yes, I am confused about a math problem. It is literally impossible in my mind! Someone please enlighten me and help me out with this problem!
Marys little brother is named Gary. When their mom gave them each some jelly beans, Gary complained "But Mary has three times as many as me!" So Mary gave him three of hers. But he still wasn't happy with the change, "Now she has twice as many as me!". How many more jelly beans will Mary have to give Gary so each one ends up having the same number of jelly beans?

So ya thanks so so so much in advance for any answers.

You have to write an equation,

Let m = Number of Mary's Jelly Beans before the trade
Let g = Number of Gary's Jelly Beans before the trade

m = 3 * g [ Mary has 3 times more than Gary]

(m - 3) = 2 * (g + 3) [ Mary minus 3 is two times more than Gary plus 3 ]

now solve for m and g,

(3g - 3) = 2g + 6
g = 9
m = 27

Now Mary gave him 3, so the numbers are now

g = 12
m = 24


Now to have the same number Mary would have to give Gary 6 more Jelly Beans.