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The average age of three people living in a house man, woman and chi
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20 May 2022, 09:00
20 May 2022, 09:00
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80% (01:56) correct
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The average age of three people living in a house – man, woman and child, is 24 years. If the man leaves and his mother stays in his place, then the average age in the house becomes 34 years. How much older is the mother than her son?
A 20
B 25
C 30
D 32
E 36
A 20
B 25
C 30
D 32
E 36
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
Re: The average age of three people living in a house man, woman and chi
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20 May 2022, 09:24
20 May 2022, 09:24
1
man = x
woman = y
child = z
Mother = m
woman = y
child = z
Therefore,
x+y+z=24*3=72 ------ (1) and
m+y+z=34*3=102 ---- (2)
(2) - (1) = m-x=30
Answer is (C)
woman = y
child = z
Mother = m
woman = y
child = z
Therefore,
x+y+z=24*3=72 ------ (1) and
m+y+z=34*3=102 ---- (2)
(2) - (1) = m-x=30
Answer is (C)
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Re: The average age of three people living in a house man, woman and chi
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21 May 2022, 06:55
21 May 2022, 06:55
1
Carcass wrote:
The average age of three people living in a house – man, woman and child, is 24 years. If the man leaves and his mother stays in his place, then the average age in the house becomes 34 years. How much older is the mother than her son?
A 20
B 25
C 30
D 32
E 36
A 20
B 25
C 30
D 32
E 36
Let M, W, and C = the ages of the man, woman, and child respectively.
Let G = the age of the man's mother.
The average age of three people living in a house – man, woman and child, is 24 years.
So, we can write: (M + W + C)/3 = 24
Multiply both sides of the equation by 3 to get: M + W + C = 72
If the man leaves and his mother stays in his place, then the average age in the house becomes 34 years.
So, we can write: (G + W + C)/3 = 34
Multiply both sides of the equation by 3 to get: G + W + C = 102
How much older is the mother than her son?
In other words, we want to find the value of G - M
We now have the following system of equations:
G + W + C = 102
M + W + C = 72
If we subtract the bottom equation from the top equation we get: G - M = 30
Answer: C
