standard_description: Construct and interpret two-way frequency tables of data when two categories are associated with each object being classified. Use the two-way table as a sample space to decide if events are independent and to approximate conditional probabilities. For example, collect data from a random sample of students in your school on their favorite subject among math, science, and English. Estimate the probability that a randomly selected student from your school will favor science given that the student is in tenth grade. Do the same for other subjects and compare the results.
problem_activity: Task
Hand span is a measure of distance from the tip of the thumb to the tip of the little finger with the hand fully extended.
Each student places his or her dominant hand on the edge of a piece of paper with the hand fully extended.
The student should make a mark at the tip of the thumb and the tip of the little finger. The distance between marks is the length of the hand span.
The student should measure his or her hand span with a centimeter ruler and round the measurement to the nearest whole centimeter.
Each student should record his or her measurement on a piece of paper.
The teacher can ask each student for his or her measurement and record the data using a line plot with a horizontal scale marked off in whole centimeters. Alternatively, the teacher can set up the line plot and ask each student to come record his or her own hand span, showing the students how by recording the teacher's hand span.
Students should comment about patterns they observe the line plot and write or discuss the answers to these two questions:
What are the largest and smallest spans?  What is the difference between the largest and smallest spans?
Use words to describe the shape of the data set.  Does it appear taller in the center like a mountain?  Are there peaks in more than one place?  Is the shape of the data flat like a table top?  Are there gaps?  Are some hand spans much bigger or smaller than the others?


aligns: no