# Probability models

Practice creating probability models and understand what makes a valid probability model.
You might need: Calculator

### Problem

Dalia owns a gravel pit. She took a random sample of rocks and counted 58 sedimentary rocks, 213 metamorphic rocks, and 522 igneous rocks.
Use the observed frequencies to create a probability model for Dalia randomly selecting one rock from her gravel pit.
Input your answers as fractions or as decimals rounded to the nearest hundredth.
Type of rockEstimated probability
Sedimentary
Metamorphic
Igneous