How to decrease the number 280
by 15% of its value?
Value of Percentage Decrease. New Value
- A percentage value is nothing but a fraction with a denominator of 100:
- 15% = 15/100 = 15 ÷ 100 = 0.15
- ...
- To decrease a positive number, subtract from it the 'Value of Percentage Decrease'.
- To decrease a negative number, don't subtract from it, but add to it the 'Value of Percentage Decrease'.
- ...
Value of Percentage Decrease =
Percentage of the Decrease % × The original value =
15% × 280
New Value =
The original value - Value of Percentage Decrease =
280 - (15% × 280)
1. Calculate the End Value
decreased by a percentage of its Initial Value
End Value =
280 - Value of Percentage Decrease =
280 - (15% × 280) =
280 - 15% × 280 =
(280 is a common factor)
(1 - 15%) × 280 =
(100% - 15%) × 280 =
85% × 280 =
85 ÷ 100 × 280 =
85 × 280 ÷ 100 =
23,800 ÷ 100 =
238
2. Calculate the absolute difference between the End Value and the Original Value
The Absolute Difference =
End Value - The original value =
238 - 280 =
- 42
3. 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 =
15% × 280
The second method:
Value of Percentage Decrease =
The original value - New Value
Value of Percentage Decrease =
42
The end value: 280 decreased by 15% percent = 238
The Absolute Difference = - 42
Value of Percentage Decrease = 42