Do Now 4/20/10 Take out HW from last night. Copy HW in your planner. Text p. 792, #1-8 all Text p. 793, #1-6 all Copy HW in your planner. Text p. 355, #8-24 evens

Skills Review Handbook “Angles and Measurement” There are 4 types of angles: Acute angle – has a measure of less than 90° Right angle – has a measure of exactly 90° Obtuse angle – has a measure of more than 90° Straight angle – has a measure of exactly 180°

Skills Review Handbook “Angles and Measurement” Use a protractor to measure an angle.

Skills Review Handbook “Units of Measurement” Text p. 792, #1-8 all Text p. 793, #1-6 all 1) 38° 2) 134° 3) 84° 4) 52° 5) 6) 7) 8) 1) 92°; obtuse 2) 180°; straight angle 3) 61°; acute 4) 157°; obtuse 5) 126°; obtuse 6) 135°; obtuse 55° 168° 90° 77°

Chapter 7 “Percents” Section 7.1 “Percents and Fractions” Section 7.2 “Percents and Proportions” Section 7.3 “Percents and Decimals” Section 7.4 “The Percent Equation” Section 7.5 “Percent of Change” Section 7.6 “Percent Applications” Section 7.7 “Simple and Compound Interest”

Objective SWBAT find a percent of change in a quantity

Section 7.5 “Percent of Change” Percent of change indicates how much a quantity increases or decreases with respect to the original amount. The percent of change of a quantity is given by: The percent is a PERCENT of INCREASE if the quantity increased and it is a PERCENT of DECREASE if the quantity decreased. Amount of change Original amount x 100

Amount of change Original amount x 100 Before: 30 After: 45 The percent of change of a quantity is given by: Amount of change Original amount x 100 Find the percent of increase or decrease (round to the nearest tenth of a %). Before: 30 After: 45 50% increase Before: 115 After: 46 60% decrease Before: 116 After: 146 25.9% increase

Amount of change Original amount x 100 The percent of change of a quantity is given by: Amount of change Original amount x 100 The enrollment of Howell Middle School South in 2006-2007 was 1100 students. In the year 2007-2008 the enrollment was 1300 students. What is the percent of increase or decrease between the two years? From 2006-2007 to 2007-2008 the enrollment increased by 200, therefore our answer is a percent of increase. 2007-2008: 1300 2006-2007: – 1100 change: 200. ≈0.181818 actual change original amount 200 1100 Percent of increase = ≈18% increase

Amount of change Original amount x 100 The percent of change of a quantity is given by: Amount of change Original amount x 100 There were 2.2 million computers used in public schools in 1991 and 2 million in 1990. Find the percent of increase. From 1990 to 1991 the number of computers used increased by 0.2 million or 200,000. 1991: 2.2 million 1990: - 2.0 million change: 0.2 million or 200,000. amount of change original amount 0.2 million 2 million =0.1 Percent of increase = =10% increase

Who is Watching MTV??? Find the percent of change from 1985 to 1987. Decrease 31.25% Increase 24%

Using a Percent of Change There were about 198,000 spectators at the NCAA Final Four in 1995. The number of spectators increased by about 12% from 1995 to 2002. About how many spectators were there in 2002? Spectators in 2002 = Spectators in 1995 + Amount of increase = 198,000 + (12% · 198,000) = 198,000 + 23,760 = 221,760

Using a Percent of Change In 1983, the average price of CD was $21.50. By 2000, the average price had decreased by 34.8%. What was the average price of a CD in 2000? Price in 2000 = Price in 1983 x Percent of change = $21.50 x (100% – 34.8%) = $21.50 x 65.2% = $14.018 = $14.02

24 Homework Text p. 355, #8-24 evens

Homework Why Did the Sea Monster Eat 27 Ships Carrying Potatoes? NOBODY CAN EAT JUST … ONE POTATO SHIP What Magic Trick Did Poof the Great Perform When He Visited Helsinki? HE VANISHED INTO FINN AIR