Ok, im guessing that this is all about mean
First mean is just adding everything up for example:
5+5+10+10+5
so the answer is 35, but that isnt completely finished you need to divide 35 by 5, or how many numbers were added then you get the mean for my example the mean is 7
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ACTUAL PROBLEMS
1. 10+15+14+8+18+11+12+12+10+10+17+16 = 153
153/12= 12.75
2. 16.4+17.1+17.4+18.1= 69 B)
69/4=17.25
3. 11+15+19+17+23+20+17+13+18+21=174
174/11=15.8181818182
4. 21+25+36+16+32= 130
130/5=26
a
