Final answer:
Kira can determine the amount of ribbon she used by multiplying the number of bracelets made on each day by the amount of ribbon used for each bracelet and adding the two products together.
Step-by-step explanation:
Kira is making 4 bracelets on Thursday and 3 bracelets on Friday. She uses 5/6 yard of ribbon for each bracelet. To determine the amount of ribbon she used, Kira can multiply the number of bracelets she made on each day by the amount of ribbon used for each bracelet, and then add the two products together. This can be expressed as the equation (4 x 5/6) + (3 x 5/6) = r. Therefore, option A is correct.
Kira can also find the total number of bracelets made by adding the number of bracelets made on Thursday and Friday, and then multiplying that sum by the amount of ribbon used for each bracelet. This can be expressed as the equation 7 x 5/6 = r. Therefore, option E is also correct.