Question

60% of 25 student are good in study. how many are not good in study? ​

Answer 1

In context to questions asked

We have to determine the value of number of students who are not good in study

As per questions

It is given that

60% of 25 students are good in study.

means, rest percentage of the students are not good in study

So, (100 - 60) = 40% of students are not good in study.

Now calculating 40% of 25,

We will get

$\frac{40}{100} \times 25 \\ = > \frac{1000}{100} \\ = > 10$

Hence 10 students are not good in study.

Answer 2

As per the details provided in the above question,  

The total number of people is 25,

60% are good in study,  

We have to find how many are not good in study.  

Thus, the number of people are good in a study is as follow,

$=\frac{60}{100}\times 25\\=0.6\times 25\\=15$

Therefore 15 students are good in study,

The students not good in a study is total students minus number of student good in study,

$=25-15=10$

Hence 10 peoples are not good in study.