Maryland Math 7.DS.C.6

7.DS.C.6 is a cluster heading. These are the individual standards under it.

• 7.DS.C.6.c

  Compare probabilities from a model to observed data and explain possible reasons for any differences.

01

What Students Need to Do

Students calculate probabilities when outcomes are equally likely. They also use trial counts to estimate probabilities, compare those estimates with predictions, and explain differences.

02

What Mastery Looks Like

For a fair die, a student finds the chance of an even roll as 3/6. Given 17 even rolls in 40 trials, they use 17/40 as an estimate and explain that random variation can cause the difference.

03

Common Misconceptions

Students may assume every color in a bag has the same chance, even when the bag holds more of one color. They may divide an observed count by the number of possible outcomes instead of the number of trials. Some think any difference between a prediction and the results proves the model is wrong.

04

How to Assess It

Exit ticket: A spinner has four equal sections and lands on red 6 times in 20 spins. Give the model probability and the observed estimate for red, then explain why they differ.

1. 01

   Make a four-section paper spinner, predict the chance of blue, spin 40 times, and compare predicted and observed fractions.

2. 02

   Present 9 heads in 20 coin flips and have students write whether that proves the coin is unfair, with a reason.

3. 03

   Give pairs die-event cards and 30-roll tally cards; have them match each event to its predicted and observed probabilities.

4. 04

   Use a 20-day bus arrival chart; count late buses and estimate the chance the next bus will be late.

• 7.DS.C.5

  Understand and apply long-run relative frequency to approximate probabilities and make predictions about chance events.