Answers

2015-09-20T11:03:16+05:30
Tick = 10dB
Chirp = 30dB
Soft Conversation = 50dB
Loud Conversation = 70dB
Chainsaw = 100dB
Loud Music = 120dB
Nearby Jet = 140dB
Steelwork Machinery = 140dB
Blue Whale Grunt = 170dB
Atomic Detonation = 200dB

Mean = \frac{sum}{count}
Mean = \frac{30+50+70+100+120+140+140+170+200}{10}
Mean = \frac{1020}{10}
Mean = 102

Median is Middle Number
Here, medians are 100 and 120.
Find mean to get single median.
120+100 = 210
210÷2 = 105
Median = 105

Mode is the numbe that reccurs most. 
140 comes twice and is the largest repetition.
Modal Value = 140

Ans : Mean=102  Median=105 Mode=140


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