Question

marks obtained by a student in 6 subjects are 84 , 91 , 72 , 68 , 87 and 78 find arithmetic mean using short cut method​

Answer 1

Explanation:

$in \: increasing \: order \\ 68 < 72 < 78 < 84 < 87 < 91 \\ even \: number \: so.. \\ \frac{n}{2} = median \\ \frac{6}{2} \\ = 3rd \: term \: is \: median \: \\ i.e \: 78$