Transcript Jennifer, Faith, Ross, Bethany and Jacob are all planning

Place Value
1,000 100 10
1
0.1
0.01 0.001 0.0001
Jennifer, Faith, Ross, Bethany and Jacob are all planning to make
lasagna. Each of them are going to the store to buy ingredients. Below
are the items that they will need.
Grocery List
1 Box of lasagna $ 3.00
1 Package of Ground beef $10.00
1 Container of Parmesan cheese$ 3.50
1lg bag of Shredded Mozzarella cheese $ 8.00
1Can of mushrooms $.99
1Spaghetti sauce$ 2.45
Adding Decimals
Counting no additional costs, how much will the groceries cost altogether if one of
each ingredient is purchased?
Box of lasagna $ 3.00
Ground beef $10.00
Parmesan cheese$ 3.50
Shredded Mozzarella cheese $ 8.00
Can of mushrooms $.99
Spaghetti sauce$ 2.45
To add the numbers with decimals, line up all of the decimal points and then add as
shown below
3.00
10.00
3.50
8.00
2.45
+ 0.99
Commonly used terms and symbols
used in comparing numbers
Less than
Greater than
Equal to
<
>
=
All five friends bought a few items that
weren’t on their lists! Faith and Jennifer
wanted to compare their totals to see who
spent less money at the grocery store.
Jennifer
Faith
Ross
Bethany
Jacob
$42.10
$42.50
$42.00
$40.70
$46.10
Lets Compare totals between Faith
and Jennifer
Line Up Decimal Points
Faith:
$42.50
Jennifer: $42.10
Add zeroes if you need to!
Start at the left and find the first place where the digits are different.
Jennifer’s spent less than Faith
42.1<42.5
How much more did Faith spend?
$ 42.50
$- 42.10
$ .40
Order items from least to
greatest
Box of lasagna $ 3.00
Ground beef $10.00
Parmesan cheese$ 3.50
Shredded Mozzarella cheese $ 8.00
Can of mushrooms $.99
Spaghetti sauce$ 2.45
• First, line up the decimal points
3.00
10.00
3.50
8.00
0.99
• Second, add zeroes if needed.
• Finally, compare the decimals.
Always start from the left!!
Equivalent Decimals
• Decimals that name the same number
are called equivalent decimals
• Lets consider 0.60 and 0.6
• Do you think these decimals are
equivalent?
• In fraction form, they are 60/100, and
6/10.
0.60
0.6
=
Multiply
• Jacob decided that he needs three times the amount of sauce.
How much will this cost him?
• $2.45
x
3
$7.35
Box of lasagna $ 3.00
Ground beef $10.00
Parmesan cheese$ 3.50
Shredded Mozzarella cheese $ 8.00
Can of mushrooms $.99
Spaghetti sauce$ 2.45
Divide
• Ross decided to go back to the store and stock up on
Parmesan cheese, he spent a total of $14.00. How many
containers of Parmesan cheese did he buy?
• In this case we would need to divide $14.00 by the price
of each Parmesan cheese container $3.50.
• Answer=Ross bought 4 containers of Parmesan cheese
Example 1
In this case, the decimal is only in the dividend (the number on the inside)
Example 2
In this case, the decimal is in both the dividend and the
divisor and must be moved as shown.
Example 3
Resources
Photos retrieved from the following websites, they also contain
helpful information if you would like to check them out!
• www.coolmath.com
• www.teach-nology.com
http://students.norledgemaths.com/rounding-to-decimalplaces.html