Could anyone please give me some example to understand this question?? I am confused..
Which of the following procedures is alwasys equivalent to adding 5 numbers and then deviding the sum by 5?
I. Multiplying the 5 numbers and then finding the 5th root of the product.
II. Adding the 5 numbers, doubling the sum, and then moving the decimal point one place to the left.
III. Ordering the 5 numbers numerically and then selecting the middle number.
A) None
B) I only
C) II only
D) III only
E) I and III
The answer is C
easy question NO2 from disclosure
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method 1 - suppose we have numbers 4 8 9 27 1;so fifth root of product is 6
but adding them all then divide by 5 is not equal to 6
method 2-suppose a b c d e are any 5 inteers so sum is a+ b+ c+ d +e
and doubling it is 2(a+ b+ c+ d +e) the divide by 10 is {a+ b+ c+ d +e}/5
method 3-
again take 4 8 9 27 1 so middle no. is 8
hence u c only second is correct
but adding them all then divide by 5 is not equal to 6
method 2-suppose a b c d e are any 5 inteers so sum is a+ b+ c+ d +e
and doubling it is 2(a+ b+ c+ d +e) the divide by 10 is {a+ b+ c+ d +e}/5
method 3-
again take 4 8 9 27 1 so middle no. is 8
hence u c only second is correct
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Thank you so much for your help.
it becomes very clear but one part... (sorry very basic)
as for the method 1
the product of the example 5 numbers: 4 8 9 27 1 will be 7776, and how come 5th root of 7776 is 6??
Thank you...
it becomes very clear but one part... (sorry very basic)
as for the method 1
the product of the example 5 numbers: 4 8 9 27 1 will be 7776, and how come 5th root of 7776 is 6??
Thank you...
-
- Master | Next Rank: 500 Posts
- Posts: 484
- Joined: Sun Jul 30, 2006 7:01 pm
- Thanked: 2 times
- Followed by:1 members