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What is the mean of all the two-digit positive integers?
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31 May 2022, 02:00
31 May 2022, 02:00
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Question Stats:
80% (01:16) correct
20% (01:12) wrong based on 5 sessions
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What is the mean of all the two-digit positive integers?
50
54
54.5
55
55.5
50
54
54.5
55
55.5
Part of the project: GRE QCQ & PS 3 Questions Every One DAILY Challenge - (2022)
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GRE Math Essentials for a TOP Quant Score - Q170!!! (2021)
GRE Geometry Formulas for a Q170
GRE - Math Book
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
GRE Math Essentials for a TOP Quant Score - Q170!!! (2021)
GRE Geometry Formulas for a Q170
GRE - Math Book
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Re: What is the mean of all the two-digit positive integers?
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31 May 2022, 06:49
31 May 2022, 06:49
1
For any evenly-spaced set of numbers, the median and the mean will be the same. To calculate the median (and therefore the mean), all we have to do is this:
(first + last)/2
Given that all two-digit positive integers have a spacing of one, then these qualify as evenly-spaced. The first two-digit positive integer is 10 and the last is 99.
Here we only need to apply
(first + last)/2 = (10+99)/2 = 109/2 = 54.5. Answer C.
(first + last)/2
Given that all two-digit positive integers have a spacing of one, then these qualify as evenly-spaced. The first two-digit positive integer is 10 and the last is 99.
Here we only need to apply
(first + last)/2 = (10+99)/2 = 109/2 = 54.5. Answer C.
Re: What is the mean of all the two-digit positive integers?
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01 Jun 2022, 14:47
01 Jun 2022, 14:47
1
To calculate the sum of n number of integers, we use (n/2)*(F#+L#)
n: No. of numbers
F#: First number
L#: First number
Mean= sum of all integers/number of integers = [(88/2)*(109)]/88 = 54.5
The answer is (C)
n: No. of numbers
F#: First number
L#: First number
Mean= sum of all integers/number of integers = [(88/2)*(109)]/88 = 54.5
The answer is (C)
