Find the number of cookies:
[tex]\text {Cookies = } 1 \dfrac{1}{2} \text { dozens}[/tex]
Since 1 dozen = 12:
[tex]\text {Cookies = } 1 \dfrac{1}{2} \times 12[/tex]
Change to improper fraction:
[tex]\text {Cookies = } \dfrac{3}{2} \times \dfrac{12}{1} [/tex]
Simplify:
[tex]\text {Cookies = } 18[/tex]
18 cookies were sold in 1/3 hour:
[tex] \dfrac{1}{3} \text { hour = } 18 \text { cookies}[/tex]
[tex] \text {1 hour = } 18 \times 3 \text { cookies}[/tex]
[tex] \text {1 hour = } 54 \text { cookies}[/tex]
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Answer: Unit rate for cookies sold = 54/hour
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