Answer: Measures of variability are used to characterize how the data are spread around the mean of the distribution.
Step-by-step explanation:The measures of average such as the median and mean represent the typical value for a dataset.However , In the dataset the actual values usually differ from one another and from the average value itself.
In this case the measure of spread, sometimes also called a measure of dispersion, is used to describe the variability in a sample or population around the mean .
Rectangular prism
is right
6.375 is greater than 6.333
Answer:
Step-by-step explanation:
12a)To rationalize the denominator, multiply the denominator and numerator by √5.
![\frac{15}{\sqrt{5}}=\frac{15*\sqrt{5}}{\sqrt{5}*\sqrt{5}}\\\\=\frac{15\sqrt{5}}{5}\\\\=3\sqrt{5}](https://tex.z-dn.net/?f=%5Cfrac%7B15%7D%7B%5Csqrt%7B5%7D%7D%3D%5Cfrac%7B15%2A%5Csqrt%7B5%7D%7D%7B%5Csqrt%7B5%7D%2A%5Csqrt%7B5%7D%7D%5C%5C%5C%5C%3D%5Cfrac%7B15%5Csqrt%7B5%7D%7D%7B5%7D%5C%5C%5C%5C%3D3%5Csqrt%7B5%7D)
b) (a+b)² = a² + 2ab + b²
(1 +√3)² = 1² + 2*1*√3 + (√3)²
= 1 + 2√3 + 3
= 4 + 2√3
a = 4 ; b =2
13) (a + b)(a - b) = a² - b²
![\frac{(6-\sqrt{5})(6+\sqrt{5})}{\sqrt{31}}=\frac{6^{2}-(\sqrt{5})^{2}}{\sqrt{31}}\\\\ =\frac{36-5}{\sqrt{31}}\\\\=\frac{31}{\sqrt{31}}\\\\=\frac{31*\sqrt{31}}{\sqrt{31}*\sqrt{31}}\\\\=\frac{31\sqrt{31}}{31}\\\\=\sqrt{31}](https://tex.z-dn.net/?f=%5Cfrac%7B%286-%5Csqrt%7B5%7D%29%286%2B%5Csqrt%7B5%7D%29%7D%7B%5Csqrt%7B31%7D%7D%3D%5Cfrac%7B6%5E%7B2%7D-%28%5Csqrt%7B5%7D%29%5E%7B2%7D%7D%7B%5Csqrt%7B31%7D%7D%5C%5C%5C%5C%20%3D%5Cfrac%7B36-5%7D%7B%5Csqrt%7B31%7D%7D%5C%5C%5C%5C%3D%5Cfrac%7B31%7D%7B%5Csqrt%7B31%7D%7D%5C%5C%5C%5C%3D%5Cfrac%7B31%2A%5Csqrt%7B31%7D%7D%7B%5Csqrt%7B31%7D%2A%5Csqrt%7B31%7D%7D%5C%5C%5C%5C%3D%5Cfrac%7B31%5Csqrt%7B31%7D%7D%7B31%7D%5C%5C%5C%5C%3D%5Csqrt%7B31%7D)