Here is the answer:
n+n+1+n+2
=3n+3. Hope it help!
[tex]<span>1\dfrac{1}{7}=\dfrac{1\cdot7+1}{7}=\dfrac{8}{7}\\\\1\dfrac{1}{7}:\dfrac{1}{9}=\dfrac{8}{7}:\dfrac{1}{9}=\dfrac{8}{7}\cdot\dfrac{9}{1}=\dfrac{72}{7}[tex]
Answer: 1 1/7 : 1/9 = 72 : 7
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Step-by-step explanation:
hope it helps . please give brainliest