Question

If the mean heights of three groups of students consisting of 20,16 and 14 students are 167m, 150m and 1.40m respectively find the mean height of all the student. ​

Answer 1

The heights should be

• 1.67m,1.5m,1.4m as it's looking general and possible

Find mean

`\\ \rm\Rrightarrow Mean=(1.67(20)+1.5(16)+1.4(14))/(14+16+20)`

`\\ \rm\Rrightarrow Mean=(77)/(50)`

`\\ \rm\Rrightarrow Mean=1.54m`

Answer 2

1.54 m

Explanation:

Given information:

Three groups of students

• 20 students with a height of 1.67 m
• 16 students with a height of 1.50 m
• 14 students with a height of 1.40 m

⇒ Total number of students = 20 + 16 + 14 = 50

To find the mean height of all the students, divide the sum of all the students' heights by the total number of students:

`\begin{aligned}\implies \sf mean\:height & =((20 * 1.67)+(16 * 1.50)+(14 * 1.40))/(50)\\\\ & = (33.4+24+19.6)/(50)\\\\ & = (77)/(50)\\\\ & = 1.54\:\: \sf m\end{aligned}`

Therefore, the mean height of all the students is 1.54 m