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Bunuel
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In 10 years, Bill will be twice as old as Jeffery. Today, Bill is 4 ti 29 Jun 2021, 08:30
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D
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

5% (low)

Question Stats:

91% (01:19) correct 9% (01:21) wrong based on 81 sessions

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In 10 years, Bill will be twice as old as Jeffery. Today, Bill is 4 times as old as Jeffery. How old is Bill?

A. 12
B. 16
C. 18
D. 20
E. 24
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D
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BrentGMATPrepNow
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In 10 years, Bill will be twice as old as Jeffery. Today, Bill is 4 ti 29 Jun 2021, 08:38
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Bunuel
In 10 years, Bill will be twice as old as Jeffery. Today, Bill is 4 times as old as Jeffery. How old is Bill?

A. 12
B. 16
C. 18
D. 20
E. 24
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Today, Bill is 4 times as old as Jeffery
Let J = Jeffery's PRESENT age
So, 4J = Bill's PRESENT age

In 10 years, Bill will be twice as old as Jeffery.
Since we already know each person's PRESENT age, we know the following...
J + 10 = Jeffery's age IN 10 YEARS
4J +10 = Bill's age IN 10 YEARS

If Bill is twice as old as Jeffrey in 10 years we can write: 4J + 10 = 2(J + 10)
Expand to get: 4J + 10 = 2J + 20
Solve to get: J = 5

So, Jeffery's PRESENT age is 5
Since 4J = Bill's PRESENT age, we know that Bill's PRESENT age = 4(5) = 20

Answer: D
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In 10 years, Bill will be twice as old as Jeffery. Today, Bill is 4 ti 29 Jun 2021, 08:42
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Bunuel
In 10 years, Bill will be twice as old as Jeffery. Today, Bill is 4 times as old as Jeffery. How old is Bill?

A. 12
B. 16
C. 18
D. 20
E. 24
Show more

Let current age of Bill be B and Jeffery be J.

Given: B = 4J
Also given:

B + 10 = 2(J + 10)
4J + 10 = 2J + 20
J = 5
So, B = 4J = 4 * 5 = 20. IMO, (D)!
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In 10 years, Bill will be twice as old as Jeffery. Today, Bill is 4 ti 29 Jun 2021, 08:55
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Bunuel
In 10 years, Bill will be twice as old as Jeffery. Today, Bill is 4 times as old as Jeffery. How old is Bill?

A. 12
B. 16
C. 18
D. 20
E. 24
Show more
Now, \(b = 4j\)

In 10 years from now, \(b + 10 = 2(j + 10)\)

Or, \(4j + 10 = 2j + 20\)

Or, \(2j = 10\)

So, \(j = 5\) , thus \(b = 20\), Answer must be (D)
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In 10 years, Bill will be twice as old as Jeffery. Today, Bill is 4 ti 29 Jun 2021, 09:20
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Bunuel
In 10 years, Bill will be twice as old as Jeffery. Today, Bill is 4 times as old as Jeffery. How old is Bill?

A. 12
B. 16
C. 18
D. 20
E. 24
Show more

An interesting question on Bill Gates and Jeff Bezos :lol: . Atleast Bill seems to topple Jeff in age! Jokes apart, here below I have attached an image that shows my approach
To find:
4J
As I glanced through options, I realised that the option C is eliminated since it is not a multiple of 4.It didn't help in this question however such observation does tend to help.
Option D is the ans
Attachments

Bill Gates and Jeff Bezos.jpeg
Bill Gates and Jeff Bezos.jpeg [ 81.79 KiB | Viewed 2761 times ]

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In 10 years, Bill will be twice as old as Jeffery. Today, Bill is 4 ti 12 May 2024, 03:21
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