Answer:
54 cents
Step-by-step explanation:
The cost of bookmarks relating to the number of bookmarks is shown in the coordinate grid. x represents the number of bookmarks and y represents the cost of each bookmark in cents.
The equation of a line passing through the points
is given by:
![y-y_1=\frac{y_2-y_1}{x_2-x_1}(x-x_1)](https://tex.z-dn.net/?f=y-y_1%3D%5Cfrac%7By_2-y_1%7D%7Bx_2-x_1%7D%28x-x_1%29)
From the coordinate grid, it has the points (2, 30) and (7, 90). Therefore, the equation is:
![y-30=\frac{90-30}{7-2}(x-2)\\\\y-30=12(x-2)\\\\y-30=12x-24\\\\y=12x+6](https://tex.z-dn.net/?f=y-30%3D%5Cfrac%7B90-30%7D%7B7-2%7D%28x-2%29%5C%5C%5C%5Cy-30%3D12%28x-2%29%5C%5C%5C%5Cy-30%3D12x-24%5C%5C%5C%5Cy%3D12x%2B6)
Therefore the cost of 4 bookmarks (x = 4):
y = 12(4) + 6
y = 48 + 6
y = 54 cents
Answer:
She bought 24 erasers
Step-by-step explanation:
$2.64 ÷0.11=24