Question

find the class mark of classes 10 - 25 and 35 - 55

Answer 1

please see the above attachment

Answer 2

$\boxed {\pink { Class \: mark = \frac{ Lower \:limit + Upper \:limit }{2} }}$

$i)Class \:mark \: of \: class (10-25 )\\= \frac{10+25}{2} = \frac{35}{2} = 17.5$

$ii)Class \:mark \: of \: class \: (35-55) \\= \frac{35+55}{2}=\frac{90}{2} = 45$

Therefore.,

$\red{ Class \: mark \:of \: 10-25} \green {= 17.5}$

$\red{ Class \: mark \:of \: 35-55} \green {= 45}$

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