Question

In a classroom of Maths there are 40% boys. In final examinations, 75% of boys got the marks greater than 80 and and 45% of total students got the marks greater than 80. Calculate, what fraction of girls got the marks equal to or less than 80.

Options

3/4

9/20

3/10

3/5

3/20


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Answer 1

let us assume that their are total 100 students in the maths class

so it means their are total 40 boys

it is given that 75% boys got more then 80 marks

which means total 30 boys got more then 80 marks

and now it is given that total 45% students got 80 marks

which means total 45 students got more then 80 marks

this shows that 15 girls got more then 80 marks

so 15% girls got more then 80%

Answer 2

Answer:

3/4

Step-by-step explanation:

let us assume there are 100 students in a class.

no of boys = 40

no of girls = 60

ATQ, 75% boys scored > 80% .

therefore, 75% of 40 = 30 boys

no of girls scored more than 80% = 15

no of girls scired less than or equal to 80 = 60-15 = 45

ratio = 45/60 = 3/4