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Ratio - A comparison of two quantities by division. Ratios can be written three different ways:. FRACTION. WORDS 3 to 5, 6 out of 7. COLON 3:5, 6:7. Most Ratios can be written using two different relationships: Part to Part Part to Whole.
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Ratio - A comparison of two quantities by division Ratios can be written three different ways: FRACTION WORDS 3 to 5, 6 out of 7 COLON 3:5, 6:7
Most Ratios can be written using two different relationships: Part to Part Part to Whole
Ratios can be represented by decimals as well. Divide the top term by the bottom term This gives you a value to represent the given relationship. The ratio of the length to width of a given rectangle is 3 to 2. How many times bigger is the length than the width? So the length is 1.5 times bigger than the width.
Equivalent ratios are like equivalent fractions - you multiply (or divide) both the top term and the bottom term by the same number. The ratio will remain equal.
In this school 1 out of three people are blonde haired and blue eyed, if this ratio holds true for this class, then how many blonde haired blue eyed kids should be in this class?
Ratios and Rates Remember: A ratio is a comparison of two different quantities using division RATE - ratio of two quantities using different units. Examples: Miles per hour, feet per second, cost per item UNIT RATE - Rate where the bottom term is equal to 1 Your heart beats 120 times in 1 minute. What is your heart rate in beats per second? Make the bottom term equal to 1. HOW? Your heart rate is 2 beats per second UNIT RATE RATE
$8.25 1 hour The unit rate is , or $8.25 per hour. Unit Rates and Proportional Reasoning COURSE 2 LESSON 5-2 Find the unit rate: earn $33 for 4 hours of work. dollars 33 Divide the first quantity by the second quantity. = 8.25 hours 4 5-2
30 min = 0.5 hConvert 30 minutes to hours. 0.5 + 3 = 3.5 Add the remaining hours. miles 203 hours 3.5 Unit Rates and Proportional Reasoning COURSE 2 LESSON 5-2 Sarah drove 203 mi to her cousin’s house. The drive took her 3 h 30 min. What was her average speed in miles per hour? Step 1: Convert the time to a single unit. The drive took 3.5 hours. Step 2: Write the ratio of miles to hours. Use a calculator to divide. = 203 3.5 58 Sarah’s average speed was 58 mi/h. 5-2
price number of lb $.89 3 $.30/lb price number of lb $1.59 5 $.32/lb Unit Rates and Proportional Reasoning COURSE 2 LESSON 5-2 Find each unit price. Then determine the better buy. 3 lb of potatoes for $.89 5 lb of potatoes for $1.59 Divide to find the unit price of each size. Since $.30 < $.32, 3 lb of potatoes for $.89 is the better buy. 5-2
HOMEWORK 5-1 #1-17,19-22, 30 You may use a calculator, but you need to show your work.