Question

Kellogg increases the length of their rectangular Pop-Tarts by 10% and decreases thewidth by 10%. By what percent willthe area of their Pop-Tarts change?ANo changeB1% decreaseс21% increaseD19% decrease

Answer 1

Let the initial length and width Kellogg's rectangular Pop-Tarts be represented as l and b

The area of the initial rectangular Pop-Tarts will be

$\begin{gathered} A_{rec\tan gle}=length\text{ }\times width \\ A_{i\text{nitial}}=l\times b \end{gathered}$

If the new length is increased 10% of the initial length, then the new length L will be

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