Unit Conversions1 foot = 12 inches

4 feet = 4 x 12 inches = 48 inches

1 centimeter = 10 millimeters

10 centimeters = ? millimeters

Unit Conversions1 pound = 16 ounces

5 pounds = ? ounces

32 ounces = ? pounds

Introduction to Algebra

Terms QuizProduct

Sum

Difference

Quotient

A. Subtraction

B. Multiplication

C. Division

D. Addition

VariableA variable is a letter that represents an

unknown number.Example

15 people are on the bus, x people are going to get off the bus at the next stop.

x is our variable, because we don’t know what it will be.

ExpressionsWe can use variables to help us solve word

problems.

To solve a word problem we need to change the words into a math expressions.

Practice7 more than a number7 + n

7 less than a numbern – 7

A number separated into 6 groupsn ÷ 6

More PracticeThe sum of a number and 10n + 10

The product of a number and 44n (same as 4 x n)

The difference of 10 and a number10 - n

Story Problems

• 15 people are on the bus, x people are going to get off the bus at the next stop. How many people will be left on the bus?

• What expression would we use to solve this?

OperationWhen people get off a bus what happens to

the total number of people on the bus?

Will we need addition, subtraction, multiplication, or division?

Expression: 15 – x = total people on bus

Try This One!Best Buy needs to purchase D number of

DVD’s. Each DVD costs $15. Write an expression that shows how much Best Buy spends on DVD’s.

Answer$15 x D = total money

We can use this expression for any number of DVD’s Best Buy buys.