Answer:
B. 10
Step-by-step explanation:
First, we need to recognize that the two triangles are similar (the triangle with a leg value of 21 and the triangle with a leg value of 4 and hypotenuse x)
Let's first label the leg of the second triangle as y.
Then, we can set up this equation
Cross multiplying gives us
84=y^2
So, y=sqrt(84) or 2 sqrt(21).
Now, using the pythagorean theorem, we get
4^2+2sqrt(21)^2=x^2
100=x^2
x=10
Treating the data as a Venn set, it is found that:
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I am going to say that:
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9 are good in all of the three courses.
This means that:
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13 are good in both mathematics and psychology
This means that:
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15 are good in both mathematics and in English
This means that:
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16 are good in both English and psychology
This means that:
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20 are good in psychology
This means that:
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45 are good in mathematics
This means that:
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Question a:
, which means that 26 students are good in mathematics only.
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Question b:
At least one is:
Thus, 80 - 52 = 28
28 students are not good in any of the three courses.
A similar problem is given at: brainly.com/question/22003843