Variable Expressions

Match the word problem with the expression:
A battery box contains 18 batteries.  Every toy needs the same number of batteries.  I was able to replace the batteries in 9 toys.  How many batteries did each toy need?  

• 9 ⋅ u = 18
• 18 - u = 9
• 18 = 9 + u
• 18 ÷ u = 9

Match the word problem with the expression:
A teacher had 16 students.  She needed to split up her class into a number of equal groups.  When she was finished, she had 4 groups.

• f x 4 = 16
• 16 x 4 = f
• f = 16 ÷ 4
• 16 ÷ f = 4

Write an expression to represent the following statement.

"a number divided by 9."

Which expression shows how many pieces of Laffy Taffy my 4 friends and I each get?

• c/4

• 4c

• c/5

• 5c

What are the variables of x+y-9

• +

• 9

• -

• x, y

A/An _____________ is a symbol, usually a letter that stands for an unknown number.

• equation

• algebraic expression

• variable

• inequality

Which of the following terms means "subtract"?

• the difference between

• less than

• decreased by

• per

• equal groups of

Which expression represents the statement "a number more than 7"?

• x + 7

• x - 7

• 7 - x

• 7 + x

Which expression correctly shows "5 less than a number"?

• y + 5

• 5 - y

• y - 5

Nate has 6 fewer CDs than Emily.  If c represents the number of CDs Emily has, which expression tells how many CDs Nate has?

• 6-c
• 6+c
• c-6
• c+6