Answer:
$61.25
Explanation:
The quantity for a 60-day supply is 60 times the 1-day usage. The BOGO offer means the sale price is effectively half the usual price.
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One day supply: 2/3 can + 1/2 can = (4/6 +3/6) = 7/6 can
60-day supply: 60 × 7/6 can = 70 cans
Susan will be paying for 70/2 = 35 cans of dog food. (She will get 35 cans free.) So, her cost will be ...
35 × $1.75 = $61.25
The cost of Susan's dog food purchase would be $61.25 before tax.