The average height of 15 girls out of a class of 60 is 138 cm. and that of the remaining girls is 142 cm. The average height of the whole class is :	Choose the correct choice from the following answers
A) 132 cms  B) 141 cms  C) 142 cms  D) 152 cms  E) 161 cms
Explanation:   Average height of the whole class =(15×138+45×142/60)=141 cms   Answer 141 cms
<result>B</result>
The average height of 15 girls out of a class of 60 is 138 cm. and that of the remaining girls is 142 cm. The average height of the whole class is :