Question

75 of 20 students are good in maths . How many sre not good in maths

Answer 1

The question posted doesn't make sense.

Well if the question is:

20 of 75 students are good in maths, how many are not good in maths?

then there can be a valid answer.

Here we subtract the number of students who are good in maths from the total number of students.

We subtract because we need to find the rest of the student's count.

This count is the same as the no of students who are not good in maths.

Number of students who are not good in maths = total number of students -number of students who are good in maths .

=75-20.

=55.

Therefore 55 of the students are not good in maths .

Answer 2

Your question needs a correction.


Correct question : 75% of 20 students are good in maths . How many are not good in maths ?




Solution : —



Given that 75% of 20 students are good in maths, it means that remaining students are not good in maths.





Number of students who are not good in maths = total number of students - number of students who are good in maths.


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Total % of anything is 100% or can be written as 1. In the total number is 20 , so it will be 100% of 20.

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Therefore,


Students who are not good in maths = 100% of 20 - 75% of 20


Students who are not good in maths = 20( 100% - 75% )


Students who are not good in maths = 20( 25% )


Students who are not good in maths = 20 × 25 / 100


Students who are not good in maths = 5

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