How to decrease the number - 9
by 12% of its value?
Value of Percentage Decrease. New Value
- A percentage value is nothing but a fraction with a denominator of 100:
- 12% = 12/100 = 12 ÷ 100 = 0.12
- ...
- To decrease a negative number, don't subtract from it, but add to it the 'Value of Percentage Decrease'.
- To decrease a positive number, subtract from it the 'Value of Percentage Decrease'.
- ...
Value of Percentage Decrease =
Percentage of the Decrease % × The original value =
12% × - 9
New Value =
The original value - Value of Percentage Decrease =
- 9 + (12% × - 9)
1. Calculate the End Value
decreased by a percentage of its Initial Value
End Value =
- 9 + Value of Percentage Decrease =
- 9 + (12% × - 9) =
- 9 + 12% × - 9 =
(- 9 is a common factor)
(1 + 12%) × - 9 =
(100% + 12%) × - 9 =
112% × - 9 =
112 ÷ 100 × - 9 =
112 × - 9 ÷ 100 =
- 1,008 ÷ 100 =
- 10.08
2. Value of Percentage Decrease
It can be calculated in two ways.
The first method:
Value of Percentage Decrease =
Percentage of the Decrease % × The original value =
12% × - 9
The second method:
Value of Percentage Decrease =
The original value - New Value
Value of Percentage Decrease =
1.08
The end value: - 9 decreased by 12% percent = - 10.08
Value of Percentage Decrease = 1.08