You visited us 1 times! Enjoying our articles? Unlock Full Access!

Byju's Answer

Standard IX

Mathematics

Properties of Measures of Central Tendency

The average h...

Question

The average height of the students in a class of $10$ is $105$ cm. If $20$ more students with an average height of $120$ cm join the class, what will the new average height be?

105

No worries! We‘ve got your back. Try BYJU‘S free classes today!

110

No worries! We‘ve got your back. Try BYJU‘S free classes today!

112

No worries! We‘ve got your back. Try BYJU‘S free classes today!

115

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

Open in App

Solution

The correct option is D $115$ cm
Total height of $10$ students $= 10 \times 105 = 1050 c m$
Total height of $20$ students $= 20 \times 120 = 2400 c m$
$∴$ total height of $30$ students $= 1050 + 2400 = 3450$
Hence average height of $30$ students $= \frac{3450}{30} = 115 c m$

Suggest Corrections

Similar questions

Q. The average height of

10

students in a class is

105 c m s

. If

20

more students with an average height of

120 c m s

join them what will be the average height be?

Q. Average height of

15

students of class

6

140 c m

and average height of

10

students of class

7

145 c m

. What is the average height of the student of both the classes?

Q. 5 students of a class have an average height

150 cm

and variance

18 {cm}^{2}

. A new student, whose height is

156 cm

, joined them. The variance

(in {cm}^{2})

of the height of these six students is:

Q. 5 students of a class have an average height

150 cm

and variance

18 {cm}^{2}

. A new student, whose height is

156 cm

joined them. The variance

(in {cm}^{2})

of the height of these six students is:

The average height of 13 girls in a class is $144 \frac{8}{13}$ cm. The average height of 11 boys in the class is $169 \frac{5}{11}$ cm. There are only 24 students in the class. What is the overall average height (in cm) of all the students together in the class?

Join BYJU'S Learning Program

The average height of the students in a class of 10 is 105 cm. If 20 more students with an average height of 120 cm join the class, what will the new average height be?

The correct option is D 115 cmTotal height of 10 students =10×105=1050cmTotal height of 20 students =20×120=2400cm∴ total height of 30 students =1050+2400=3450Hence average height of 30 students =345030=115cm

The average height of the students in a class of $10$ is $105$ cm. If $20$ more students with an average height of $120$ cm join the class, what will the new average height be?

The correct option is D $115$ cm
Total height of $10$ students $= 10 \times 105 = 1050 c m$
Total height of $20$ students $= 20 \times 120 = 2400 c m$
$∴$ total height of $30$ students $= 1050 + 2400 = 3450$
Hence average height of $30$ students $= \frac{3450}{30} = 115 c m$