John is 20 years older than Brian. 12 years ago, John was twice as old

Question

John is 20 years older than Brian. 12 years ago, John was twice as old as Brian. How old is Brian?

A. 20
B. 24
C. 28
D. 32
E. 36

what's wrong with this word translation ??'

J= B + 20

J-12=2 (B+8)

Bunuel · Answer

John is 20 years older than Brian --> J=B+20;
 12 years ago , John was twice as old as Brian --> J-12=2*(B-12);

Solving: B=32.

P.S. Please type in the questions which contain only the plain text rather than attach the screenshot.

ScottTargetTestPrep · Answer

We can let John’s age today = j and Brian’s age today = b, and we can create the following equation:

j = b + 20

We see that 12 years ago, John’s age was (j - 12) and Brian’s age was (b - 12). We know that at that time, John was twice as old as Brian. Thus, we have:

j - 12 = 2(b - 12)

j - 12 = 2b - 24

j = 2b - 12

We have two equations for b. Equating them, we have:

b + 20 = 2b - 12

32 = b

Slicerad · Answer

12 years ago:
Let Brian from 12 years ago equal X.

John = 2X

NOW:
Brian = X+12
John = 2X+12 OR X+12+20

Let 2X+12 = X+12+20
Thus X = 20

Substitute back into the equation:
Brian now: 20+12=32

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Nipungupta9081 · Answer

Answer D

J = 20 + B

J - 12 = 2 ( B - 12 )

Putting value of ' J '

20 + B - 12 = 2B - 24
 
8 + B = 2B - 24

B = 32

MathRevolution · Answer

John is 20 years older than Brian => John = Brian + 20  ---------------(1)

12 years ago, John was twice as old as Brian => (John - 12) = 2 (Brian - 12)
 
 => John - 12 = 2 Brian - 24
 
 => John = 2 Brian -12  ---------------(2)

From (1) and (2),

=> Brian + 20 = 2 Brian - 12

=> 20 + 12 = Brian

=> Brian = 32

Answer D

tahaakkawi · Answer

J = B+20
J = 2B-12

so, 2B-12 = B+20 
and we get B = 32 and to make sure we plug in 
J = 32+20 = 52

John is 20 years older than Brian. 12 years ago, John was twice as old

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John is 20 years older than Brian. 12 years ago, John was twice as old

Prep Toolkit

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