GRE Prep Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
GRE Prep Club Team Member
Joined: 20 Feb 2017
Posts: 2508
Given Kudos: 1053
GPA: 3.39
The mean of (54,820)^2 and (54,822)^2 =
[#permalink]
26 Nov 2022, 02:01
26 Nov 2022, 02:01
Expert Reply
00:00
Question Stats:
60% (01:42) correct
40% (00:54) wrong based on 5 sessions
Hide Show timer Statistics
The mean of \((54,820)^2\) and \((54,822)^2 =\)
(A) \((54,821)^2\)
(B) \((54,821.5)^2\)
(C) \((54,820.5)^2\)
(D) \((54,821)^2 + 1\)
(E) \((54,821)^2 – 1\)
(A) \((54,821)^2\)
(B) \((54,821.5)^2\)
(C) \((54,820.5)^2\)
(D) \((54,821)^2 + 1\)
(E) \((54,821)^2 – 1\)
GRE Prep Club Team Member
Joined: 20 Feb 2017
Posts: 2508
Given Kudos: 1053
GPA: 3.39
Re: The mean of (54,820)^2 and (54,822)^2 =
[#permalink]
27 Nov 2022, 21:03
27 Nov 2022, 21:03
Expert Reply
Shrink the monster technique.
The two numbers are two consecutive even numbers raised to 2. Shrink the monster and think of baby numbers such as 0 and 2.
\(mean=\frac{{0^2 + 2^2}}{2}=2\)
Substitute you baby numbers to the answer choices.
(A) \({0+1}^{2}=1\) Eliminate!
(B) \({0+1.5}^{2}=2.25\) Eliminate!
(C) \({0+0.5}^{2}=0.25\) Eliminate!
(D) \({0+1}^{2}+1=2\) Bingo!
(E) \({0+1}^{2}-1=0\) Eliminate!
Answer: D
The two numbers are two consecutive even numbers raised to 2. Shrink the monster and think of baby numbers such as 0 and 2.
\(mean=\frac{{0^2 + 2^2}}{2}=2\)
Substitute you baby numbers to the answer choices.
(A) \({0+1}^{2}=1\) Eliminate!
(B) \({0+1.5}^{2}=2.25\) Eliminate!
(C) \({0+0.5}^{2}=0.25\) Eliminate!
(D) \({0+1}^{2}+1=2\) Bingo!
(E) \({0+1}^{2}-1=0\) Eliminate!
Answer: D
Re: The mean of (54,820)^2 and (54,822)^2 =
[#permalink]
10 Dec 2022, 05:47
10 Dec 2022, 05:47
2
Let x=54821
54822²+54820²=(x-1)²+(x+1)²=
=x²-2x+1 + x²+2x+1=2x²+2
Mean= 2(x²+1)/2= x²+1
Recall that x=54821
Hence mean= 54821²+1
Posted from my mobile device
54822²+54820²=(x-1)²+(x+1)²=
=x²-2x+1 + x²+2x+1=2x²+2
Mean= 2(x²+1)/2= x²+1
Recall that x=54821
Hence mean= 54821²+1
Posted from my mobile device
