Question

the average score of 60 student in a test is 70. the ratio of number of boys so that the girls is 11:4. the avg. score of boys is 10% more than that of girls. the average score of girls is

Answer 1

Answer:

here it is , average score of girls is x which is 65.22

Answer 2

The average score of girls is 65.22 .

Given:

The average score of 60 students in a test is 70.

The ratio of the number of boys so that the girls is 11:4.

The avg. score of boys is 10% more than that of girls.

To Find:

We  have to find the average score of girls

Solution:

The total score of 60 students is (60*70)=4200

There are $60*\frac{11}{15}=44$ boys in the class.

There are $60*\frac{4}{15} = 16$ girls in the class.

Let us assume that the avg. score of girls is x.

Then the total score of girls is 16x.

So, the avg score of boys is $\frac{110x}{100}$.

Then the total score of boys is $\frac{110x}{100} * 44 = \frac{242x}{5}$.

Therefore,

$16x+\frac{242x}{5} =4200$

⇒$\frac{322x}{5} = 4200$

⇒$x=65.22$

Hence, the average score of girls is 65.22 .

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