Question

Three percent of $ 4200 $ is equal to $ 6 $ percent of what number?
A. $ 8400 $
B. $ 2100 $
C. $ 1260 $
D. $ 252 $
E. $ 126 $

Answer 1

Hint: Percent: Percent or percentage is used in mathematics as the number or ratio which is expressed as a fraction of a hundredth. And this is followed by the sign ‘%’. Percentage has no dimension. Hence it is called dimensionless. Every percentage variable has three possible unknown variables: percentage, part, base.
To solve this we should apply the basics of percentage. First find the value of the given value of the percentage given then we take a variable. Calculate the value of the variable as per the given condition and choose the correct option as per asked in question.

Complete step by step solution:
Given,
The number is $ 4200 $
According to the question
$ 3\% \,of\,4200\,is\, $
Now solve
 $ = \dfrac{3}{{100}} \times 4200 $
Simplify
 $ = 3 \times 42 $
 $ = 126 $
It is equal to the $ 6\% $ of some number
 $ 6\% \,of\,x\,is\,126 $
 $ \Rightarrow \dfrac{6}{{100}} \times x = 126 $
Simplify
 $ \Rightarrow 6x = 126 \times 100 $
 $ \Rightarrow x = \dfrac{{126 \times 100}}{6} $
 $ \Rightarrow x = 2100 $
So the answer is (B) $ 2100 $ .
So, the correct answer is “Option B”.

Note: Percentage is widely used in profit and loss. It is also used to show statistics data to increase or decrease in data by how much percentage. The percentage function takes the form z is equal to the x percent of number y. Taking a percent can be viewed as the same operation as multiplication by a fraction.
We can get this answer by using trial and error method for which we have to separately calculate its given percentage as per maintained in the question after that we can also cross check our given answer as calculated by the above method.