Answer: C: 4/$7.76=13/x
Step-by-step explanation:
Set them proportionally equal. Glue stick numbers on top, and the cost for them below. Since you do not know the cost of 13 glue sticks, x, representing the cost of the glue sticks goes on the bottom. then, you have
4/$7.76=13/x
4 = 13
7.76 = x
You can multiply 13*$7.76, which equals $100.88.
Then, divide $100.88 by 4. You should get $25.22.
Therefore, 13 glue sticks equal $25.22.