Review: Fractions and Ratios Learning Goal: To activate relevant information from grades 7-10
Warm-Up: Problem of the Day In a photograph, Jackson is standing next to his Dodge Viper. The Viper is actually 3.8 m long but appears 4.5 cm long in the photograph. If Jackson appears 2.7 cm tall in the photograph, what is his actual height?
Fractions and Ratios Fractions and Ratios are both proportions that compare two things. – A ratio of 15 boys to 18 girls in a class 15:18 – 22 right answers out of 25 questions 22/25 Note: fractions are usually used to compare a number of something to the total
Equivalent Fractions and Ratios When both terms in a fraction or ratio are multiplied or divided by the same number, it’s value remains the same; this is important for reducing to lowest terms. 1) 2)1:2 = 2:4 = 4:8
Practice – Equivalent Fractions A student in Mrs. Rickert’s class scores 90/120 on their final exam. Because the final exam is worth 30%, Mrs. Rickert must enter a score out of 30. What is the student’s mark out of 30?
Practice – Equivalent Ratios A standard solution used in the chemistry lab contains a 7:4 ratio of water to hydrochloric acid. If Ms. Skinn has 52mL of acid, how much water should she add to make this solution?
Brainteaser of the Day! Arrange 10 plates on a rectangular table so that there are 3 plates on each side.