We have 3 elements here CP-cost price, SP-selling price, and profit percentage Profit%.
So the equations relating them are:

Profit=SP-CP (for loss its CP-SP)

Profit%=((SP-CP)/CP)*100

Solution:
Since we don’t know the cost of the article it is ok to assume a value initially.
Let the CP of each article =1 unit.
CP of 20 articles =20 units
SP of x articles=CP of 20 articles= 20 units
SP of 1 article = 20/x
using formula Profit%=((SP-CP)/CP)*100 for 1 article as profit% is a constant for each article.
25=[(20-x)/x)]*100
=> 25x/100 = 20-x
=> x/4 = 20-x
=> 5x=80
solving we get x=16 units.

We have 3 elements here CP-cost price, SP-selling price, and profit percentage Profit%.
So the equations relating them are:

Profit=SP-CP (for loss its CP-SP)
Profit%=((SP-CP)/CP)*100

Solution:
Since we don’t know the cost of the article it is ok to assume a value initially.
Let the CP of each article =1 unit.
CP of 20 articles =20 units
SP of x articles=CP of 20 articles= 20 units
SP of 1 article = 20/x
using formula Profit%=((SP-CP)/CP)*100 for 1 article as profit% is a constant for each article.
25=[(20-x)/x)]*100
=> 25x/100 = 20-x
=> x/4 = 20-x
=> 5x=80
solving we get x=16 units.

chandana says

can tell me how

Saran Harika says

Profit%= (purchased qty – selleing qty)/selling qty × 100

25=(20-x)/x *100

1/4=(20-x)/x

x=80–4x

5x=80

x=16

chandana says

can you tell me how

Saran Harika says

We have 3 elements here CP-cost price, SP-selling price, and profit percentage Profit%.

So the equations relating them are:

Profit=SP-CP (for loss its CP-SP)

Profit%=((SP-CP)/CP)*100

Solution:

Since we don’t know the cost of the article it is ok to assume a value initially.

Let the CP of each article =1 unit.

CP of 20 articles =20 units

SP of x articles=CP of 20 articles= 20 units

SP of 1 article = 20/x

using formula Profit%=((SP-CP)/CP)*100 for 1 article as profit% is a constant for each article.

25=[(20-x)/x)]*100

=> 25x/100 = 20-x

=> x/4 = 20-x

=> 5x=80

solving we get x=16 units.