Calculating Gear Ratios

Competency C: Understand and Use Numbers
Task Group C3: Use measures
Level: 3
At this level, learners: Use measures to make multi-step calculations; use specialized measuring tools

Performance Descriptors
The learner:

• Calculates using numbers expressed as whole numbers, fractions, decimals, percentages, and integers
• Calculates the radius, diameter, and circumference of circles
• Understands and uses properties of angles and triangles to solve problems
• Understands and uses formulas for finding the perimeter, area, and volume of non-rectangular, composite shapes
• Manages unfamiliar elements (e.g. context, content) to complete tasks
• Makes estimates involving many factors where precision is required
• Interprets and represents measurements taken with specialized tools (e.g. callipers, multimeters)
• Chooses and performs required operations; makes inferences to identify required operations
• Selects appropriate steps to solutions from among options
• Identifies a variety of ways to complete tasks
• Interprets, represents, and converts measures using whole numbers, decimals, percentages, ratios, and fractions
• Organizes and displays numerical information (e.g. graphs, tables)
• Uses strategies to check accuracy (e.g. estimating, using a calculator, repeating a calculation, using the reverse operation)

Task Descriptors

• Scope of task may not be clearly defined
• May include unfamiliar elements (e.g. context, content)
• Requires multi-step calculations where one step builds on the previous step
• Requires the use of rates or common formulas or both
• May require converting measurements to make calculations
• May involve documents (e.g. rate tables, scale drawings)
• May require converting between whole numbers, decimals, fractions, ratios, and percentages
• May require converting between measurement systems or between units in one system

ESKARGO:
Embedded Skills, Knowledge and Attitudes Reference Guide for Ontario – C3.3