Ratios, Fractions, and Percents A ratio is sometimes a part-to-part comparison of two numbers measured in the same units. A bag contains 6 yellow marbles, 3 red marbles, 5 green marbles, and 4 blue marbles. The Ratio of Red marbles to Blue marbles is 3 to 4, 3:4, ¾.

Ratios, Fractions, and Percents A ratio is sometimes a part-to-part comparison of two numbers measured in the same units. A bag contains 6 yellow marbles, 3 red marbles, 5 green marbles, and 4 blue marbles. The Ratio of Red marbles to Blue marbles is 3 to 4, 3:4, ¾.

5 yellow, 3 red, 5 green, 4 blue What is the ratio of yellow to red marbles? What is the ratio of blue to green marbles? A fraction is a part-to-whole comparison. A percent is also a part-to-whole comparison. What fraction of the bag is red? What percent of the bag is red? What fraction of the bag is blue? What percent of the bag is blue?

RATES A rate is a comparison of two quantities measured in different units. Suppose you read 230 words in two minutes, your reading rate would be 230 words 2 mins

Unit Rates A unit rate is a rate that has a denominator of one. words 230 =÷ 2 115 words minutes 2 ÷ 2 1 minute The unit rate is 115 words/min (115 words per minute) To find Unit Rates divide the numerator by the denominator. Find the unit rate a.) travel 1,200 miles in 4 hours b.) score 98 points in 6 games c.) write 11 pages in 2 hours d.) run 400 meters in 1 min 30 seconds

Unit Rates cont. The comparisons: “45 miles per gallon,” “$3.50 per hour,” “8.5 kilometers per hour,” and “two sandwiches for each person,” are all unit rates. “Per gallon” means “for one gallon” and “Per hour” means “for one hour.”

Unit Price A unit price is the price per unit of an item. (The price for 1.) To find the unit price, divide the price by the size of the item. Find the unit price: a.) $12 for 4 yd b.) $9 for 5 fl oz c.) 4 m for $10 d.) 20 lbs for $7

Determining the Better Buy To determine the better buy find each unit price then compare them. Find each unit price. Then determine the better buy. detergent: 32 fl oz for $1.99 50 fl oz for $2.49 ribbon: 1 yd for $.49 3 yd for $1.95 popcorn: 15oz for $1.69 30 oz for $2.99

A proportion is an equation that states two ratios are equal. In the proportion 6 = 12 8 16 The products 6●16 and 8●12 are called cross products. If two ratios form a proportion, their cross products are EQUAL. Which pairs of ratios form a proportion? a.)3 , 6 b.)6 , 4 c.)4 , 5 d.)6 , 9 8 16 9 6 8 9 10 15

Maps and Scale Drawings A scale drawing is an enlarged or reduced drawing of an object. You use a map’s scale and proportions to find actual distances. The scale of a map is 2 cm = 15 km. Find the actual distance for the following map distances. a.)8 cm b.)1.3cm c.)15.5cm *d.) 5mm