The heights of 500 students at a local school were recorded and found to be approximated by the normal curve below. Which

Mathematics

1 answer:

Sunny_sXe [5.5K]3 years ago

5 0

Answer:

option C.

Step-by-step explanation:

The given graph is the bell shaped graph.

From the graph we can observe that the peak is at 69.

So, the mean of the data is = 69 .

Standard deviation is the deviation of the graph from the mean value.

= 72-69 = 3

Hence, the standard deviation is equal to 3.

So, the correct answer is option C.

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1. 8y^2-4y+1 divided by 2y-1

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Q1. The answer is $4y+ \frac{1}{2y-1}$

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Q2. The answer is $2a+3+ \frac{6}{a-1}$

$\frac{2 a^{2}+a+3 }{a-1} = \frac{a*2a-2a+3a+3}{a-1} = \frac{2a(a-1)+3a+3}{a-1}= \frac{2a(a-1)}{a-1}+ \frac{3a+3}{a-1} = \\ \\ =2a+ \frac{3a+3}{a-1}=2a+ \frac{3a-3+3+3}{a-1}=2a+ \frac{3(a-1)+6}{a-1} =2a+ \frac{3(a-1)}{a-1} + \frac{6}{a-1}= \\ \\ =2a+3+ \frac{6}{a-1}$


Q3. The answer is $2 x^{2} +5x+2$ 

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Q4. The answer is 2x + 7

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