Re: In a class, 10% of the girls have blue eyes, and 20% of the
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01 Jul 2020, 23:01
Using the ratio we can assume that the amount of girls is 3k and the amount of boys is 4k. As a result the total amount of students is 7k.
10% of girls have blue eyes can be expressed as (0.1 x amount of girls)=0.1x3k= 0.3k
20% of boys have blue eyes can be expressed as (0.2 x amount of boys)=0.2x4k= 0.8k
Summing both numbers we obtain that the amount of blue-eyed students is 1.1k
So the fraction of students that have blue eyes is 1.1k/7k
Reducing and multiplying it by 10
We obtain 11/70.
Answer: A