Answer-
18
Explanation-
THEY USED PROCESS OF MULTIPLICATION SO THAT BY 2, BUT THEN DIVIDE 36 BY 2.
x = (a - 2x)/6z
a = 2x + 6xz
-2x -2x
a - 2x = 6xz
/6z /6z
(a - 2x)/6z = x
Answer:
9 sleeves for 22.99
Step-by-step explanation
The first pack has a unit rate of $11.49/ 4 balls
=$2.8725
The second pack has a unit rate of $16.79/6balls
=$2.798 per ball
the third pack has a unit rate of $22.99/9balls
=2.554
So, I would definitely go for the third pack since it has the least cost.