Which of the following distribution of numbers has the greatest standard deviation?
(A) {-3, 1, 2}
(B) {-2, -1, 1, 2}
(C) {3, 5, 7}
(D) {-1, 2, 3, 4}
(E) {0, 2, 4}
I'm confused between A and D. Can any experts help?
Which of the following distribution of numbers has the great
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Hello.
Let's take a look at your question.
We first need to calculate the mean value of each set of numbers:
$$M_A=0;\ M_B=0;\ M_C=5;\ M_D=2;\ M_E=2.$$
Now, we have to calculate the standard deviation of each set of numbers:
$$SD_A=\sqrt{7};\ SD_B=\sqrt{\frac{10}{3}};\ SD_C=2;\ SD_D=\sqrt{\frac{14}{3}}\ and\ SD_E=\ 2.$$
So, set A has the greatest standard deviation.
The correct option is A.
You can discard option D because $$7>14/3,\ so\ \sqrt{7}>\sqrt{\frac{14}{3}}.$$
I hope this explanation can help you.
Let me know if you have another doubt.
I'm available if you'd like a follow up.
Let's take a look at your question.
We first need to calculate the mean value of each set of numbers:
$$M_A=0;\ M_B=0;\ M_C=5;\ M_D=2;\ M_E=2.$$
Now, we have to calculate the standard deviation of each set of numbers:
$$SD_A=\sqrt{7};\ SD_B=\sqrt{\frac{10}{3}};\ SD_C=2;\ SD_D=\sqrt{\frac{14}{3}}\ and\ SD_E=\ 2.$$
So, set A has the greatest standard deviation.
The correct option is A.
You can discard option D because $$7>14/3,\ so\ \sqrt{7}>\sqrt{\frac{14}{3}}.$$
I hope this explanation can help you.
Let me know if you have another doubt.
I'm available if you'd like a follow up.
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