How to decrease the number 20
by 75% of its value?
Value of Percentage Decrease. New Value
- A percentage value is nothing but a fraction with a denominator of 100:
- 75% = 75/100 = 75 ÷ 100 = 0.75
- ...
- 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 =
75% × 20
New Value =
The original value - Value of Percentage Decrease =
20 - (75% × 20)
1. Calculate the End Value
decreased by a percentage of its Initial Value
End Value =
20 - Value of Percentage Decrease =
20 - (75% × 20) =
20 - 75% × 20 =
(20 is a common factor)
(1 - 75%) × 20 =
(100% - 75%) × 20 =
25% × 20 =
25 ÷ 100 × 20 =
25 × 20 ÷ 100 =
500 ÷ 100 =
5
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 =
75% × 20
The second method:
Value of Percentage Decrease =
The original value - New Value
Value of Percentage Decrease =
15
The end value: 20 decreased by 75% percent = 5
Value of Percentage Decrease = 15