Exercise 1 Page 228

Let's first find the price of one bracelet b. From the table we know that the cost of 10 bracelets is $9 which we can express by the equation: 10b=9.If we divide both sides of the equation by 10, we can find the price of one bracelet:

One bracelet costs $0.90. Now we can write a general equation. If we multiply the cost of one bracelet by the number of bracelets b, we get the total cost c. We write this as the equation c=0.9b. This corresponds to option B.