Question

University students were surveyed randomly in their opinion regarding a recent tuition increase. The minimum age required with 18 the maximum age is 45. Use the range rule of thumb to estimate the standard deviation of the ages.

Answer 1

Solution: We are given that the minimum age required is 18 and the maximum age required is 45.

The range rule of thumb states that range is about four times the standard deviation.

$Range \approx 4 \times s$

Where s denotes the standard deviation.

$\therefore s \approx \frac{Range}{4}$

        $\approx \frac{45-18}{4}$

        $\approx \frac{27}{4}$

        $\approx 6.75$

Therefore, using the range rule of thumb, the standard deviation is 6.75

Answer 2

The answer is actually 6.8.