Understanding 9

Multiply x * . () by nine:
9 groups of or 9 lots of
Skip count in 9s
Triple the number then triple again
Learn your 9 times tables
For 1 to 9x9 the answer is 1 less than the non 9 number and the number that adds to make 9 e.g. 9x8=72 so 7 is 1 less than 8 and you add 2 to 7 to get nine
Times by 10 and take one of the non 9 number away

Divide ÷ / by nine:
How many times does 9 go into
Break into 9 groups
One ninth of
Skip count in 9s and count the 9s
Keep subtracting 9 from the number 18-9-9=0 so 9 goes into 18 exactly 2 times
Reverse your 9 times tables 3x9=27 so 27÷9=3 and 27÷3=9

Add + nine:
Count 9 on from the original number
Add 10 then take 1
Add 5 then add 4

Take - nine:
Count 9 back from the original number
Take 10 then add 1
Take 6 then take 3