Answer:
40% = 0.40
Explanation:
The word "percent" literally means "per hundred". The symbol % is shorthand for the divsion /100. That is "%" and "/100" are interchangeable.
40% = 40/100 = "forty hundredths" = 0.40
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Additional comment
Division by 100 is equivalent to moving the decimal point 2 places left. For example,
1000./100 = 10.00
As a consequence, you might see instruction for converting a percentage to a decimal: "move the decimal point 2 places to the left and lose the % symbol."
This works no matter where the decimal point is:
0.034% = 0.034/100 = 0.00034