Average height

In a class are 34 students. The average height of the students is 165 cm. What will be the average height of students in the classroom when two pupils, tall 176 cm and 170 cm, move from this school/class? The average height in meters of all the students in a class and display the result in meters.

Correct answer:

x =  164.5 cm
x₂ =  1.645 m

Step-by-step explanation:

$$\begin{gathered} n_1=34 \\ {x}_1=165\text{cm} \\ s=x_1\cdot n_1-176-170=165\cdot 34-176-170=5264\text{cm} \\ n=n_1-2=34-2=32 \\ x=\frac{s}{n}=\frac{5264}{32}=\frac{329}{2}\text{cm}=164.5\text{cm} \end{gathered}$$

$x_2=x\to \text{m}=x:100\text{m}=164.5:100\text{m}=1.645\text{m}=1.645\text{m}$

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