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Given the Set A: {p, q, r, s, t\} 23 Oct 2024, 01:14
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C
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55% (01:04) correct 45% (00:58) wrong based on 115 sessions

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Given the Set A: \(\{p, q, r, s, t\}\). Which of the following options will be sufficient in finding the Standard Deviation, S.D. of set A?


I. SD of the set \(\{p+100,q+100,r+100,s+100,t+100\}\)

II. SD of the set \(\{100p,100q,100r,100s,100t\}\)

III. SD of the set \(\{\frac{p}{2}-100, \frac{q}{2}-100, \frac{r}{2}-100,\frac{s}{2}-100,\frac{t}{2}-100\}\)

A. I only
B. I and II only
C, I,II, and III
D. II and III
E. I and III
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C
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Given the Set A: {p, q, r, s, t\} 29 Oct 2024, 09:50
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Given the Set A: \(\{p, q, r, s, t\}\). Which of the following options will be sufficient in finding the Standard Deviation, S.D. of set A?


I. SD of the set \(\{p+100,q+100,r+100,s+100,t+100\}\)

II. SD of the set \(\{100p,100q,100r,100s,100t\}\)

III. SD of the set \(\{\frac{p}{2}-100, \frac{q}{2}-100, \frac{r}{2}-100,\frac{s}{2}-100,\frac{t}{2}-100\}\)

A. I only
B. I and II only
C, I,II, and III
D. II and III
E. I and III
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Why is the answer to this B and not C?

I am obviously missing something, I concluded since the set is being divided by a constant the S.D would become 1/2 and the subtraction by a constant should not have changed the S.D at all?
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Given the Set A: {p, q, r, s, t\} 30 Oct 2024, 00:21
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Ankur17000
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Given the Set A: \(\{p, q, r, s, t\}\). Which of the following options will be sufficient in finding the Standard Deviation, S.D. of set A?


I. SD of the set \(\{p+100,q+100,r+100,s+100,t+100\}\)

II. SD of the set \(\{100p,100q,100r,100s,100t\}\)

III. SD of the set \(\{\frac{p}{2}-100, \frac{q}{2}-100, \frac{r}{2}-100,\frac{s}{2}-100,\frac{t}{2}-100\}\)

A. I only
B. I and II only
C, I,II, and III
D. II and III
E. I and III
Why is the answer to this B and not C?

I am obviously missing something, I concluded since the set is being divided by a constant the S.D would become 1/2 and the subtraction by a constant should not have changed the S.D at all?
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I am confused as well
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Given the Set A: {p, q, r, s, t\} 30 Oct 2024, 01:57
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Option C must be the correct one.
I. {p + 100; q + 100; r + 100; s + 100; t + 100} Adding 100 to each element doesn't affect the SD. Thus, the SD of this set is the same as the SD of the original set.
II. {100p; 100q; 100r; 100s; 100t} Multiplying each element by 100 will increase the SD by a factor of 100. So, the SD of this set is 100 times the SD of the original set, which allows us to determine the SD of the original set by dividing by 100.
III. {p/2; q/2; r/2; s/2; t/2} Dividing each element by 2 will reduce the SD by a factor of 2. So, the SD of this set is half the SD of the original set, which allows us to determine the SD of the original set by multiplying by 2.
Therefore, statements I, II, and III each provide enough information to find the SD of the original set.
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Given the Set A: {p, q, r, s, t\} 30 Oct 2024, 05:29
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Let's take the easiest case first - II, Multiplying or dividing each number in the set will also change the SD by the same factor, so we just need to divide the SD of this set by 100 to get the SD of our target set. Eliminate A and E.

Next, adding or subtracting the same figure does not impact the SD, so SD of I and our set is the same. Eliminate E.

Now the 3rd is just dividing the figures by 2 and subtracting 100 from it, since adding or subtracting does not impact the SD, the SD of this set and the set without subtracting the 100 will be the same, now multiply this SD by 2 to get the SD of our target set. Ans C. All of them can be used to arrive at the SD of our target set.
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Given the Set A: {p, q, r, s, t\} 21 Apr 2026, 09:45
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