Six second grade students tried tossing a ball into a basket ten times each. Their teacher tl suggested a different way of tossing the ball, and the six students tried again. The numbe successful tosses, before and after the teacher's added instruction, are shown below.
$\begin{array}{c|cccccc}
\text { Student } & \mathbf{A} & \mathbf{B} & \mathbf{C} & \mathbf{D} & \mathbf{E} & \mathbf{F} \
\hline \text { Before the suggestion (out of 10) } & 6 & 5 & 6 & 2 & 6 & 5 \
\text { After the suggestion (out of 10) } & 2 & 5 & 2 & 4 & 2 & 5
\end{array}$

Find the signed rank of child A's difference. [Recall, differences of zero are not ranked.]
A) +3.5
B) +3
C) +5
D) +4

Question

Six second grade students tried tossing a ball into a basket ten times each. Their teacher tl suggested a different way of tossing the ball, and the six students tried again. The numbe successful tosses, before and after the teacher's added instruction, are shown below.
$\begin{array}{c|cccccc}
\text { Student } & \mathbf{A} & \mathbf{B} & \mathbf{C} & \mathbf{D} & \mathbf{E} & \mathbf{F} \
\hline \text { Before the suggestion (out of 10) } & 6 & 5 & 6 & 2 & 6 & 5 \
\text { After the suggestion (out of 10) } & 2 & 5 & 2 & 4 & 2 & 5
\end{array}$

Find the signed rank of child A's difference. [Recall, differences of zero are not ranked.]
A) +3.5
B) +3
C) +5
D) +4

Quizplus · Accepted Answer

To find the signed rank of child A's difference, first calculate the differences in scores before and after the suggestion for each student: A: 6 - 2 = 4, B: 5 - 5 = 0, C: 6 - 2 = 4, D: 2 - 4 = -2, E: 6 - 2 = 4, F: 5 - 5 = 0. Ignore differences of zero (B and F). Rank the absolute values of the differences: 4, 4, 4, and 2. The ranks are 2.5 (for D), and 3.5, 3.5, 3.5 (for A, C, E). Since A's difference is positive, its signed rank is +3.5.

Six Second Grade Students Tried Tossing a Ball into a Basket