A Bowling Alley Checks the Timing of the Ball Returns

Essay

A bowling alley checks the timing of the ball returns daily for four lanes.The times are given in seconds.Create X-bar and R charts.Is the process in control? $$\begin{array} { c c c c c } \text { day\ allay \# } & \mathbf { 1 } & \mathbf { 2 } & \mathbf { 3 } & \mathbf { 4 } \\\mathbf { 1 } & 15 & 17 & 15 & 17 \\\mathbf { 2 } & 17 & 16 & 18 & 21 \\\mathbf { 3 } & 16 & 15 & 14 & 16 \\\mathbf { 4 } & 19 & 16 & 19 & 18 \\\mathbf { 5 } & 15 & 17 & 15 & 20 \\\mathbf { 6 } & 15 & 14 & 14 & 19 \\\mathbf { 7 } & 16 & 18 & 17 & 18 \\\mathbf { 8 } & 18 & 15 & 18 & 20 \\\mathbf { 9 } & 15 & 16 & 15 & 17 \\\mathbf {10} & 16 & 16 & 16 & 21\end{array}$$