Question

identify the lower class limits, upper class limits, class width, class mid - points, and class boundaries in the summary.
age (yr) when award was won frequency
25 - 29 30
30 - 34 33
35 - 39 13
40 - 44 3
45 - 49 4
50 - 54 1
55 - 59 1
(type integers or decimals. do not round. use ascending order.)
identify the class width.
5
(type an integer or a decimal. do not round.)
identify the class mid - points.
(type integers or decimals. do not round. use ascending order.)

Explanation:

Step1: Recall mid - point formula

The formula for the mid - point of a class interval with lower limit $L$ and upper limit $U$ is $M=\frac{L + U}{2}$.

Step2: Calculate mid - point for first class

For the class $25 - 29$, $L = 25$, $U=29$, so $M_1=\frac{25 + 29}{2}=\frac{54}{2}=27$.

Step3: Calculate mid - point for second class

For the class $30 - 34$, $L = 30$, $U = 34$, so $M_2=\frac{30+34}{2}=\frac{64}{2}=32$.

Step4: Calculate mid - point for third class

For the class $35 - 39$, $L = 35$, $U = 39$, so $M_3=\frac{35 + 39}{2}=\frac{74}{2}=37$.

Step5: Calculate mid - point for fourth class

For the class $40 - 44$, $L = 40$, $U = 44$, so $M_4=\frac{40+44}{2}=\frac{84}{2}=42$.

Step6: Calculate mid - point for fifth class

For the class $45 - 49$, $L = 45$, $U = 49$, so $M_5=\frac{45 + 49}{2}=\frac{94}{2}=47$.

Step7: Calculate mid - point for sixth class

For the class $50 - 54$, $L = 50$, $U = 54$, so $M_6=\frac{50+54}{2}=\frac{104}{2}=52$.

Step8: Calculate mid - point for seventh class

For the class $55 - 59$, $L = 55$, $U = 59$, so $M_7=\frac{55 + 59}{2}=\frac{114}{2}=57$.

Answer:

27, 32, 37, 42, 47, 52, 57