1. August 23 rd, 2013

2.  Variable –  Is a letter that stands for a number  Variable Expression –  Is a mathematical phrase that uses variables, numerals, and mathematical symbols

3.  How many miles can you drive on ten gallons of gas? Vehicle TypeMilesGallonsMiles per Gallon Subcompact33010330 ÷ 10 Compact30010300 ÷ 10 Mid-Size Sedan24510245 ÷ 10 Sport Utility Vehicle17510175 ÷ 10 Pickup Truck16010160 ÷ 10

4.  Suppose you don’t know the number of miles, what can we do?  Use a variable! ▪ Let m = the number of miles on 10 gallons ▪ The variable expression for miles per gallon would therefore be m ÷ 10

5.  What is the difference between the above expressions?  Can you come up with an example of each?

6.  We can translate words into variable expressions Word PhraseVariable Expression Nine more than a number yy + 9 4 less than a number n A number z times three A number a divided by 12 5 times the quantity 4 plus a number c

7.  Bagels cost $0.50 each. Write a variable expression for the cost of b bagels.  Answer :0.50b