Answer:
Mean=12.5
Median=13
Step-by-step explanation:
What you do for the mean is you add all the numbers together to get 75.
You will then divide it by 6 because there are 6 numbers to get 12.5 as your answer.
The median all you do is find the middle number. The middle numbers are 12 and 14. You will take 12 and 14 and add them together to get 26.
You will then divide it by 2 to get 13 as your answer.
X+x=15 combine like terms on left side
2x=15 divide both sides by 2
x=7.5
The equation would be
x - 18 = collection left
X = how much was your collection before you gave your brother 13 cards
Since we don't know how big was your collection before, this would be the equation to solve it.
What I don’t speak that language im sorry