Welcome to class!
Hi Everyone
July 28
Review 1 Single Digit Addition: 5 + 2 = ? Two Digit Addition: - - PowerPoint PPT Presentation
Hi Everyone Welcome to class! July 28 Review 1 Single Digit Addition: 5 + 2 = ? Two Digit Addition: Review 1 Continued Doubling: 7 + 7 = ? Halving: Opposite Operations Double and half are opposite operations Addition and subtraction
July 28
Single Digit Addition: 5 + 2 = ? Two Digit Addition:
Doubling: 7 + 7 = ? Halving:
Key Words: Addition
Key Words: Subtraction
Pictographs
Graphs that have pictures instead of numbers They are easier to read We can easily find largest and smallest value To read a pictograph, we use skip counting
Method 1: Skip Counting With Chart
1 2 3 4 5 6 7 8 9 10 11 By 1 2 4 6 8 10 12 14 16 18 20 22 By 2 5 10 15 20 25 30 35 40 45 50 55 By 5 10 20 30 40 50 60 70 80 90 100 110 By 10
2 + 2 + 2 + 2 = 8 5 + 5 + 5 = 15
Splitting
41 = 40 + 1 23 = 20 + 3 18 = 10 + 8
41 + 22 = 40 + 1 + 20 + 2 = 63 57 + 32 = 50 + 7 + 30 + 2 = 89
When you add, always add the ONES and then the TENS.
41 + 22 = 63
You can recall the song.
48 - 16 = 40 + 8 - 10 - 6 = 30 + 2 = 32 50 - 2 = 40 + 10 - 2 = 40 + 8 = 48
? + 6 = 9 OR 6 + ? = 9
Reverse Operations
? = 9 - 6 = 3
Fun Fact: This is because addition is commutative. 3 + 4 = 4 + 3 = 7
EVEN + EVEN = EVEN EVEN + ODD = ODD
Your homework is the last 2 pages of today’s material as well as the puzzles. Also, please do the pictograph homework if you have not done so. If you are done those, you can do the extra word problems practice.
BONUS MATERIAL
Think of an equation as a scale. Both sides of the scale must be equal. We can add or subtract the same number from both sides, and both sides must remain equal.
This approach works for subtraction as well, although it is harder since there are two cases to consider.
23 + 23 = 20 + 20 + 3 + 3 = 46
86 / 2 = 80 / 2 + 6 / 2 = 40 + 3 = 43 96 / 2 = 80 / 2 + 16 / 2 = 40 + 8 = 48
Matt is 82 years old. Kevin is 53 years old. How much older is Matt than Kevin? In 15 years, how old will Matt be? What about Kevin? In 15 years, how much older is Matt than Kevin? 39 years ago, how old was Matt? What about Kevin? 39 years ago, how much older was Matt than Kevin?
There are 26 eggs in the house today. Each day, the amount of eggs is one half of what they were yesterday. How many eggs were there one day ago? How many eggs will be there in one day? How many eggs were there two days ago? How many more eggs were there two days ago compared to today?