Jackie is selling smoothies at a school fair. She starts the day with $15 in her cash box to provide change to her customers. If each smoothie costs $3.75, which graph represents the balance of the cash box, y, after Jackie sells x smoothies?
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Answer with Step-by-step explanation:
Jackie is selling smoothies at a school fair. She starts the day with $15 in her cash box to provide change to her customers.
Each smoothie costs $3.75, then cost of x smoothies is: $3.75x
Then, y=3.75x+15
When x=0 y=15
when x=4 y=3.75×4+15
i.e. y=30
The only graph which satisfies y=0 at x=0 and y=30 at x=4 is D.
Hence, the correct graph is:
D.