Answers

2014-05-26T11:54:45+05:30
Normal conversation 65dB
Telephone dial tone 80dB
City Traffic 85dB
Train whistle 90dB
Train Running 95dB
Hand Drill 98dB
Motorcycle 100dB
Rock Music Concert 115dB
Pneumatic machine 125dB
Jet engine 140dB

Mean = 
 \frac{65+80+85+90+95+98+100+115+125+140}{10}

         =  \frac{993}{10} = 99.3 dB

Median = Average of Two Middle most values of the data =  \frac{95+98}{2} =  \frac{193}{2} = 96.5dB   

There is no MODE for the data as none of the data is repeating.
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