To set up the inequality, we start with the amount Lily currently has from her grandfather, which is $40, and we add the amount she earns each week, which is $65 times the number of weeks she saves, represented by \( x \).
The total amount of money Lily needs is at least $300, so we can write the inequality as follows:
\[ 40 + 65x \geq 300 \]
Now, let's solve for \( x \):
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Subtract 40 from both sides:
\[ 65x \geq 300 - 40 \]
\[ 65x \geq 260 \]
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Divide both sides by 65:
\[ x \geq \frac{260}{65} \]
\[ x \geq 4 \]
Thus, the inequality is:
\[ x + 4 \geq 300 \]
This can be rewritten in the specified format as:
\[ x \geq 4 \]
Solution Description:
Lily must save for at least 4 weeks to have at least $300. This means that if she saves for 4 weeks or more, she will reach her goal of $300 or more, allowing her to buy the cellphone. Any value of \( x \) that is 4 or greater (e.g., 4, 5, 6, ...) satisfies the requirement.