Show:
Let's Get Mental
Take It Away
Add It Up
Multiply
Divide!
100

Mental Math

42+33 = 

What is 75

100

50-10 =

What is 40

100

17 + 8 = 

25

100

7 x 8 =

56

100

24/4

What is 6

200

Mental Math

7 x 7 = 


What is 49

200

16-9 = 

7

200

38 + 14 = 

52

200

50 x 2 = 

100

200

Mental Math

42 divided into 6 groups

What is 7

300

Mental Math

60 divided by 3=

What is 20

300

456-12 = 

444

300

78 + 12 =

90

300

Double the number and add once more. What rule am I?

The 3 Rule
300

MENTAL MATH

40 divided into 5 groups

What is 8

400

Mental Math

30x20 = 

What is 600

400

691 - _?_ = 52

639

400

1,234 + 2,345 + 4,567 + 7,890 =

16036

400

The four patterns for 9 trick

1. first digit count up 

2. second digit count down

3. first digit is one less than what is being multiplied by 9

4. the sum of the two digits equal to 9

400

Steps for long division: Division Family

Dad (divide), Mom (multiply), Sister (subtract), Brother (bring down), Rest (repeat/reminder)
500

Mental Math

15x2 =

30

500

There are 67 bird families living near the mountain. If 32 bird families flew away for winter, how many bird families were left near the mountain?


35

500

Two boxes filled with comic books were just delivered. If each box is filled with 120 books, how many books are there?


240

500

The 0 trick (not 0 rule)

count the number of zeros at the end of a number and add in answer, then multiply like normal

500
How are the 3 and the 9 rule for divisible similar

3 rule: sum of the digits must be divisible by 3.

9 rule: sum of the digits must be divisible by 9.