Addition
Explain the steps needed to add decimals.
* Add decimal point to whole numbers
* Line up decimals
* Place numbers in correct place value
* Put zeroes (0) as place holders
* Add right to left
Explain the steps to subtract decimals.
* Add decimal point to whole numbers
* Line up decimals
* Place numbers in correct place value
* Put zeroes (0) as place holders
* Subtract right to left
Explain how to use standard algorithm for multiplying decimals.
* Stack the numbers
* Do NOT line up the decimals
* Multiply normally (include place holder zeroes)
* Count how many values after each decimals
* Jump that number of places (right to left) in answer
Select all the expressions that have a value greater than 3. (YOU HAVE TO SOLVE FOR ALL TO FIND OUT!)
A. 1.67 + 1.4
B. 2.97 + 0.004
C. 3.017 − 0.05
D. 4.5 − 1.47
E. 5.503 − 2.52
A. 1.67 + 1.4
D. 4.5 − 1.47
7.7 x 9.9
76.23
Which estimate is closest to the actual value of (2.99548) ⋅ (1.8342)?
**Round to nearest tenth!
A. 4.8
B. 5.5
C. 6.6
D. 8.3
B. 5.5
2.99548 = 3
1.8342 = 1.8
3 x 1.8 = 5.4
Four runners are training for long races. Noah ran 5.123 miles, Andre ran 6.34 miles, Jada ran 7.1 miles, and Diego ran 8 miles.
Compared to Noah, how much farther did Jada run?
1.977 miles
One way to compute a 15% tip for a bill is to multiply it by 0.15.
A restaurant bill was $42.40. Calculate the tip.
BILL X TIP
Explain or show your reasoning.
$6.36
2.9 - 0.02
2.88
0.002 x 9.7
0.0194
For part of a science experiment, Andre adds 0.25 milliliters of food coloring to 12.3 milliliters of water. How many milliliters does the mixture contain?
Addition
12.55 milliliters
Find the difference:
1
− 0 . 4 3 0 8
Need to add placeholder zeroes!
0.5692
Find the product: (0.061) ⋅ (0.43)
0.02623
10 - 0.4
0.96
0.7 x 0.02
0.014
Four runners are training for long races. Noah ran 5.123 miles, Andre ran 6.34 miles, Jada ran 7.1 miles, and Diego ran 8 miles.
What is the total running distance of the four runners?
26.563 miles
0.89 - 0.6
0.29
Two students have different ways of calculating (2.5) ⋅ (0.44).
a. Elena says, “I find 25 ⋅ 44 and then place the decimal point.”
Show how Elena might calculate (2.5) ⋅ (0.44).
Answer: 1.1
Drop zeroes and decimals and just multiply
25 ⋅ 44 = 1,100.
2.5 has 1 value to the right of the decimal
0.44 has 2 values to the right of the decimal
1 + 2 = 3 --> jump 3 places to the left in answer
1,100 ---> 1.1
36.51 + 13.2
49.71
7.45 x 0.20
1.49
3.25 + 0.075
3.325
7 - 1.93
5.07
Two students have different ways of calculating (2.5) ⋅ (0.44).
Lin says, “I drew this diagram and then found the area of each part.”
Show how Lin might calculate (2.5) ⋅ (0.44).
0 0 0
.44 .88 .220
0 + 0 + .88 + .220 = 1.1
76.492 + 2.209
76.701
9.30 x 5
46.5