Numerical Expressions
What is a numerical expression???
How do we write one?
Numerical Expressions
• A numerical expression is a mathematical
phrase that has numbers and operational
signs but does not have a equal sign.
Numerical Expressions
• Tyler caught 15 small bass, and his dad caught
12 small bass in the Memorial Bass Tourney in
Tidioute, PA. Write a numerical expression to
represent how many fish they caught in all.
Numerical Expressions
• Choose which operation to use.
• You need to join groups of different sizes, so use
addition.
• 15 small bass + 12 small bass
•
15
+ 12
• So 15 + 12 represents how many fish they caught
in all.
Numerical Expressions
• Write an expression to match the words.
• Emma has 11 fish in her aquarium. She buys 4
more fish.
• Lucia has 128 stamps. She uses 38 stamps on
party invitations.
Numerical Expressions
• Write an expression to match the words.
• Karla buys 5 books. Each book cost $3.
• Four players share 52 cards equally.
Numerical Expressions
• Expressions with parentheses:
•
The meaning of the words in a problem
will tell you where to place the parentheses in
an expression.
•
Doug went fishing for 3 days.
Each day he put $15 in his pocket. At the end
of each day, he had $5 left. How much money
did Doug spend by the end of the week?
Numerical Expressions
• What expression can you write to show how
much money Doug spends in one day?
• (
--
)
• Now how can you show how much money
Doug spends in 3 days?
•
____ X (
-- )
Numerical Expressions
• Which problem matches the expression
•
$20 -- ( $12 + $3)
Numerical Expressions
• Kim has $20 to spend for her fishing trip. She
spends $12 on a fishing pole. Then she finds $3.
How much money does Kim have now?
• First: Kim has $20
• Next: ________________
• Then: ________________
• Does this match the expression?
Numerical Expressions
• Kim has $20 to spend for her fishing trip. She
spends $12 on a fishing pole and $3 on bait.
How much money does Kim have now?
• First: Kim has $20
• Next: __________________
• Then: ____________________
• Do these words match the expression?
Numerical Expressions
• Which matches the words?
• Teri had 18 worms. She gave 4 worms to Susie
and 3 worms to Jamie.
• (18 – 4) + 3
18 – (4 + 3)
Numerical Expressions
• Rick had $8. He then worked 4 hours for $5
each hour.
• $8 + (4 x $5)
($8 + 4) x $5
Numerical Expressions
• Write an expression to match the words.
• Greg drives 26 miles on Monday and 90 miles
on Tuesday.
• Lynda has 27 fewer fish than Jack. Jack has 80
fish.
Numerical Expressions
• Write words to match the expression.
• 34 – 17
• 6 x (12 – 4)
Numerical Expressions
• Using a variable.
• A variable is a letter or a symbol that stands for
one or more numbers.
• Write an expression with a variable.
Rona had 96 pencils and then sold some.
Tim had 17 cards. Joe gave him more.
Lee gave me 12 cookies I ate 6 and then baked
more.
Numerical Expressions
• Review Expression from textbook page 66.
• Set up notebook for # 8 to 18.