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Multiplying a 2- or 3-digit number by
16 2/3
Select a 2-digit number. (Choose larger numbers when you feel sure about the
method.)
Add two zeros to the number.
Divide by 6 (or by 2 and 3).
Example:
The 2-digit number chosen to multiply by 16 2/3
is 96.
Add two zeros: 9600.
Divide by 3: 9600/3 = 3200. (9600 is divisible by 3 because the sum of its digits
is divisible by 3.)
Divide by 2: 3200/2 = 1600.
So 96 x 16 2/3 = 1600.
See the pattern?
If the 2-digit number chosen to multiply by 16 2/3
is 76:
Add two zeros: 7600.
Divide by 2: 7600/2 = 3800.
Divide by 3: 3800 / 3 = 1266 2/3.
So 76 x 16 2/3 = 1266 2/3.
Test the number to see if it is divisible by 3. If not, divide by 2 first. With
some practice you will become adept at multiplying by 16 2/3