Question

The heights of 17 girls were measured (in cm) and the results were as follows:
143, 148, 135, 150, 128, 139, 149, 146, 132, 151, 142, 144, 156, 140, 136, 142, 133
(1) What is the height of the tallest girl?
(ii) What is the height of the shortest girl?
(ii) How many girls have height 140 cm or more? (iv) Find the mean height.​

Answer 1

Answer:

Let's first arrange the heights in ascending order:

→ 128, 132, 133, 135, 136, 139, 140, 142, 142, 143, 144, 146, 148, 149, 150, 151, 156

Coming to the first question:

i) Height of the tallest girl:

• According to the ascending order, 156 cm is the greatest value.

Hence the height of the tallest girl is 156 cm.

ii) Height of the shortest girl:

• According to the ascending order, 128 cm is the least value.

Hence the height of the shortest girl is 128 cm.

iii) How many girls have a height greater than 140 cm or more ?

→ These are the heights which are greater than or equal to 140 cm.

• 140, 142, 142, 143, 144, 146, 148, 149, 150, 151, 156

Hence 11 girls have a height greater than or equal to 140 cm.

iv) Mean height of the given data is calculated as:

$\boxed{Mean = \dfrac{\text{Sum of all heights}}{\text{Total number of girls}}}$

Sum of all heights is equal to 2,414 cm. Total number of girls, according to the question is 17.

Hence the mean height of the given data is:

$\implies \bf{ Mean = \dfrac{2414}{17}} = \bf{\boxed{142\:\:cm}}$

Answer 2

Answer:

Required Answer :-

Firstly let's see the ascending order of the results

128, 132, 133, 135, 136, 139, 140, 142, 142, 143, 144, 146, 148, 149, 150, 151, 156

1. Tallest Girl = 156 cm
2. Shortest girl = 128 cm
3. 140, 142, 142, 143, 144, 146, 148, 149, 150, 151, 156

As we know that

$\frak \red{Mean = \dfrac{Sum \: of\: observation}{total \: no \: of \: observation}}$

$\sf \: Mean \: = \cancel \dfrac{2414}{17}$

$\frak \pink{Mean \: = 142 \: cm}$