First we find the mean of the data set: M=(4+8+13+15+24+25+28)/7=16.7. Now we find the distance of each value from the mean value:
16.7-4=12.7, 16.7-8=8.7, 16.7-13=3.7, 16.7-15=1.7, 24-16.7=7.3, 25-16.7=8.3 and 28-16.7=11.3. Now we find the mean absolute deviation by finding the mean value of the distances: (12.7+8.7+3.7+1.7+7.3+8.3+11.3)/7=53.7/7=7.67. So the mean absolute value is A) 7.67.
The mistake was that in calculating only the mean value, not the mean absolute deviation.
First you simply have to substitute 2 in replace of all the a's, and -2 in replace of all of the b's
4((2)2+2(-2))
Then you want to follow the order of operations, PEMDAS (Parantheses-Exponent-Multiplication-Division-Addition-Subtraction), and multiply within the parantheses.
4(4+(-4))
Next you will add within the parantheses (So add the 4 and -4 together)
4(0)
Lastly multiply
0
Your answer is 0
Hope this helps!
Coincidentally i i hi hi oh
Answer: 197
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Explanation:
There are 28 days in February for non-leap years. We would need to select at least 28*7+1 = 197 people so that we are guaranteed that at least 8 people were born on the same day.
The worst case scenario is that we pick 7 people born on feb 1, then 7 people for feb 2, and so on til we get up to feb 28. This is a total of 28*7 = 196 people. That extra person will have to somewhere in the calendar for feb. Since its not that leapday, this extra person will make a group of 8. So that's why we need to select at least 197 people (aka 197 people or more).