Answer:
8
Step-by-step explanation:
a A + b A where A is a matrix and a and b are scalars
( a+b) A
3+5
= 8![\left[\begin{array}{cc}-1&2\\4&-5\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D-1%262%5C%5C4%26-5%5Cend%7Barray%7D%5Cright%5D)
Answer:
y=1300-285x
Step-by-step explanation:
1300-575=725
725/5=145
y=1300-285x
Answer:
cos -60° =
,
cos 660° = 
Step-by-step explanation:
hope it helps
Answer:
Explain the circumstances for which the interquartile range is the preferred measure of dispersion
Interquartile range is preferred when the distribution of data is highly skewed (right or left skewed) and when we have the presence of outliers. Because under these conditions the sample variance and deviation can be biased estimators for the dispersion.
What is an advantage that the standard deviation has over the interquartile range?
The most important advantage is that the sample variance and deviation takes in count all the observations in order to calculate the statistic.
Step-by-step explanation:
Previous concepts
The interquartile range is defined as the difference between the upper quartile and the first quartile and is a measure of dispersion for a dataset.

The standard deviation is a measure of dispersion obatined from the sample variance and is given by:

Solution to the problem
Explain the circumstances for which the interquartile range is the preferred measure of dispersion
Interquartile range is preferred when the distribution of data is highly skewed (right or left skewed) and when we have the presence of outliers. Because under these conditions the sample variance and deviation can be biased estimators for the dispersion.
What is an advantage that the standard deviation has over the interquartile range?
The most important advantage is that the sample variance and deviation takes in count all the observations in order to calculate the statistic.
Assuming the size of the whole remains constant, as you divide the whole into more pieces, each piece must be smaller. For example, when a whole is divided into four pieces vs nine pieces, 1/4 of the whole is larger than 1/9 of a whole.