2.5 solving proportions write and use ratios, rates, and unit rates. write and solve proportions
TRANSCRIPT
????
2.5 Solving Proportions
Write and use ratios, rates, and unit rates.Write and solve proportions.
????
• A ratio is a comparison of two quantities.• A ratio can be written as
????
Example: Reduce Ratios
????
Practice
????
• A rate is a ratio of two quantities with different units.
• A unit rate is a rate with a second quantity of 1 unit.
• You can convert any rate into a unit rate.
????
Example: Divide Rates
????
Practice
????
• A statement that two ratios are equal is called a proportion.
• You can solve a proportion by using the cross products property, then an inverse operation.
????
Example: Cross Multiply, Divide
????
Practice
????
• A percent is a ratio that compares a number to 100.
• You can use the following proportion to find unknown values.
????
Examples
????
Practice
????
• Proportions are used to create scale drawings and scale models.
• A scale is a ratio between two sets of measurements.
• A scale drawing or scale model uses a scale to represent an object as smaller or larger than the actual object.
????
Example
????
REVIEW
1) What is a ratio?
2) What is a rate?
3) What is a proportion?
4) What is a scale drawing?