Finding 45 percent of a number
Choose a 2-digit number.
Multiply the number by 9.
Divide by 2.
Move the decimal point one place to the left.
Example:
If the number selected is 36:
Multiply by 9: 9 × 36 = 270 + 54 = 324
Divide by 2: 324/2 = 162
Move the decimal point one place to the left: 16.2
So 45% of 36 = 16.2.
See the pattern?
If the number selected is 52:
Multiply by 9: 9 × 52 = 450 + 18 = 468
Divide by 2: 468/2 = 234
Move the decimal point one place to the left: 23.4
So 45% of 52 = 23.4.
