Fern's estimate is not correct because he rounded 548 wrong, it would be rounded to 550 instead since the number 8 is closer to 10. So the correct answer would be 420.
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:
False
Step-by-step explanation:

1/3 is the ratio of cups of water to cups of flour as a fraction (simplified)
Answer:
The answer is 3
Step-by-step explanation: