Answer:
20
Step-by-step explanation:
f(x) = 30
30 = 1.8x -5.4
35.4 = 1.8x
x = 35.4/1.8
x = 19.666
B.offer another idea hope i helped :)
Let
x-----------> the probability that someone buys a book that is paperback
y----------> the probability that someone buys a book that is a fiction
P-----> the probability that someone buys a book that is paperback and fiction
we know that



so
substitute the values

therefore
<u>the answer is the option A</u>

40 ÷ 2.40= 16.66
the teacher can buy 16 cookies