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There are 20 students in a class of them...

There are 20 students in a class of them, the height of ten students is 150 cm each, the height of 6 students is 142 cm each and the height of 4 students is 132 cm each. Find the average height of all the students.

A

144

B

140

C

138

D

146

Text Solution

Verified by Experts

The correct Answer is:
A

The average height `=(10xx150+6xx142+4xx132)/20`
`=(1500+852+528)/20=2880/20=144`
Hence, the correct option is (a).
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