To determine the range of the function \( f(x) = 40x + 57 \) for \( x \) in the context given, we need to consider the valid interval for \( x \).
Since Ellis starts collecting stamps on September 1 and loses interest after 5 weeks, the values of \( x \) will range from 0 to 5.
Now, we can calculate the minimum and maximum values of \( f(x) \) when \( x \) is in the interval [0, 5]:
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When \( x = 0 \): \[ f(0) = 40(0) + 57 = 57 \]
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When \( x = 5 \): \[ f(5) = 40(5) + 57 = 200 + 57 = 257 \]
Thus, the function \( f(x) \) takes values starting from 57 when \( x = 0 \) up to 257 when \( x = 5 \).
Given this, the range of \( f(x) \) can be described in inequality symbols as: \[ 57 \leq y \leq 257 \]
Therefore, the correct response is: 57 ≤ y ≤ 257