15. Mary is buying office supplies. She
already spent some og her budget and
now needs to buy pens for the office,
Her purchases can be modeled by the
equation: B(p) = 53 +1.75p where B(p)
is the total amount Mary spent after
buying p pens.
What is the best interpretation of the
rate of change?
a). The total amount of money Mary
spends
b). The number of pens Mary buys
c). The amount of money Mary has
already spent
d). The cost of each pen
