1. 8-1 Ratios and Proportions Learning Target: I will be able to use ratios and proportions to model and solve problems. Goal 1.02 num, num, num...

2. This is really just cross-multiplying ad=bc a b c d = __ is equivalent to Examples: x __ y = 5 6 If then 6x= 5y

3. a c b d = a b c d = __ is equivalent to Examples: x __ y = 5 6 If You're really just flipping the ratios then y __ x = 6 5

4. d b a c = a b c d = is equivalent to Examples: x __ y = 5 6 If You're taking your numerators and making them a ratio, then take your denominators and make them a ratio. then x __ 5 = y 6

5. b b d d a c = + + a b c d = is equivalent to Examples: x __ y = 5 6 If Add the denominator to the top of each ratio then x+y y __ = 5+6 6 ___

6. You can do it! Try these examples. 1. 2. 3. 4. x 5 12 7 = __ y+3 ___ 8 = y _ 4 5 _ z = 20 _ 3 18 ___ n+6 = 6 _ n 1. x=8.57 2. y=3 3. z=.75 4. n=3