Multiplication By 9, 99 And 999

 

Multiplication Of 9 With Any Number

Let’s understand this rule by taking examples. Convert 9 to (10-1)

18*9 = 18*(10-1) = 18*10-18 = 180-18 = 162

187*9 = 187*(10-1) = 1870-187 = 1683

Multiplication Of 99 With Any Number

Let’s understand this rule by taking examples. Convert 99 to (100-1) first.

46*99 = 46*(100-1) = 46*100-46 = 4600-46 = 4554

362*99 = 362*(100-1) = 36200-362 = 35838

Multiplication Of 999 With Any Number

Let’s understand this rule by taking examples. All you have to do is write 999 as (1000-1) since 1000 minus 1 is 999

66*999 = 66*(1000-1) = 66*1000-66 = 66000-66 = 65934

138*999 = 138*(1000-1) = 138000-138 = 137862