To get the answer you divide the cds by 2 because the CD's are 1/2 in thick to get: 26 in
You just multiply the numerators of the fractions and the denominators of the fractions together, and then reduce the fraction to simplify it from that point on.
The wording of this question is a bit confusing... You can't write a sequence in sigma notation, but rather a series or sum. I think the question is asking you to write the sum of the sequence,
which would be
in sigma notation.
To do this, notice that the denominator in each term is a power of 2, starting with 
and ending with 
. So in sigma notation, this series is
Answer:
Distribution 4, mean is 20 and standard deviation is 3.2
Step-by-step explanation:
The standard deviation tells us on average how far each of our data values is from the mean. A standard deviation that is larger than the others will mean a distribution that is more spread out than the others; 3.2 is the largest standard deviation, so Distribution 4 has the greatest spread.
