Rectangle 83

Rectangle land has a dimension of 8 km times 10 9/10 km. What is the area?

Write your answer as a fraction or as a whole or mixed number.

Correct answer:

A =  87 ¹⁄₅ = 436/5 km²

Step-by-step explanation:

$$\begin{gathered} a=8\text{km} \\ b=10\frac{9}{10}=10+\frac{9}{10}=\frac{10\cdot 10+9}{10}=\frac{100+9}{10}=\frac{109}{10}=10.9\text{km} \\ A=a\cdot b=8\cdot \frac{109}{10}=\frac{8\cdot 109}{10}=\frac{872}{10}=\frac{436}{5}{\text{km}}^2=87\frac{1}{5}{\text{km}}^2=87.2{\text{km}}^2 \end{gathered}$$

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