+ Ratios & Rates PS 8 -1, 8-2, Solve single-step word problems involving ratios 8-2 Solve single-step word problems involving rates 8-4 Solve/Verify multi-step word problems involving ratios/rates/ Do Now: Copy the PS/LT at the top of a new left page Under the PS/LT : Write the following as percents. 4/10 =.08 = 24/50 =

+ Ratio A comparison of two quantities by division Ratios can compare two separate quantities Can be written 3 ways a to b a a : b

+ Example A family is decorating their Christmas tree. They want to put 3 strings of lights, 15 ornaments, 2 strings of popcorn, and 1 star at the top. Write each ratio in all three forms. Ornaments to strings of lights Strings of lights to strings of popcorn Stars to total decorations to the tree Does the order matter?? 15 : 3 or 5 : 1 3 : 2, 3/2, 3 to 2 1: 21, 1/21, 1 to 21

+ Rate A ratio that compares two quantities measured in different units Jill ran 5 miles in 45 minutes Unit Rate A rate in which the second quantity in the comparison is one unit Exmaple– 5 miles in 45 minutes  Jill can run 1 mile in 9 minutes Unit rate: basically a rate with a denominator of 1

+ Example At Costco, you can buy a 10 pound bag of potatoes for $2.00. Write the rate that compares dollars to pounds: Now write the unit rate: (this answers the question– “How much does ONE pound cost?”

+ Assignment P. 262 – 263 #1-13, 15