He has 420 cards. if you have 30 packs and 14 in each just 30*14
They are both in the thousands category
You would have to estimate this and a rough estimate would be around 240
Circumference + perimeter =38
x = circumference of circle
find r in terms of x
2

r=x
r=

Area=

r^2
so..
A=

(

)^2
=

(

)
=

(38-x) is perimeter
then

(

)^2

+ (

)^2
then you graph it and it equals
16.716 cm the circumference of the circle
Let x = Barbie's number
1/3 x -20 = 72
1/3 x = 92
x = 92*3=276