Answer:
Can you show the full problem so that I can help
Given parameters:
Cost price of the article = Nu.28.30
Selling price of the article = Nu.29.30
Unknown:
Gain percentage = ?
The gain percentage is the same as the percentage profit on a trade.
The formula is given as:
Gain percentage = 
Profit = Selling price - Cost price
= Nu.29.30 - Nu.28.30
= Nu. 1
Now input the parameters and solve;
Gain percentage = 
= 3.5%
The gain percent is 3.5%
Answer:
314.2ft^2
Step-by-step explanation:
Given data
Diameter= 20ft
Radius r= 20/2= 10ft
The expression for the area is
A= πr^2
A= 3.142*10^2
A= 3.142*100
A= 314.2ft^2
Hence the area is 314.2ft^2