Three years from now, Dathan will be three times as old as E

Question

Three years from now, Dathan will be three times as old as Ellen and Ellen will be six years younger than Famke. If Dathan's age is three years less than twice Famke's age, how old is Famke?

(A) 9
(B) 15
(C) 21
(D) 27
(E) 33

GH-10.18.13 -OE to follow

Bunuel · Accepted Answer

Three years from now, Dathan will be three times as old as Ellen: D + 3 = 3(E+3) --> D = 3E + 6.

Three years from now, Ellen will be six years younger than Famke: E +3 = (F + 3) - 6 --> E = F - 6.

Dathan's age (now) is three years less than twice Famke's age: D = 2F - 3.

From (I) and (III): 3E + 6 = 2F - 3 --> 3E = 2F - 9. 
Since from (II) E = F - 6, then 3(F - 6) = 2F - 9 --> F = 9.

Answer: A.

Bunuel · Answer

Similar "age" problems to practice: today-rose-is-twice-as-old-as-sam-and-sam-is-3-years-younger-131477.html jack-is-now-14-years-older-than-bill-if-in-10-years-jack-144435.html age-problem-m03q13-74810.html if-father-s-age-is-1-less-than-twice-the-son-s-age-what-is-126832.html john-is-20-years-older-than-brian-12-years-ago-john-was-132135.html 8-years-ago-george-was-half-as-old-as-sarah-sarah-is-now-132076.html in-ten-years-david-will-be-four-times-as-old-as-aaron-twen-104243.html roy-is-now-4-years-older-than-erik-and-half-of-that-amount-90386.html Hope it helps.

avohden · Answer

Official Explanation

Answer: A   Three years from now, Dathan's age will be d + 3, Ellen's will be e + 3, and Famke will be f + 3. Thus, three years from now, (d + 3) = 3(e + 3), and (e + 3) = (f + 3) - 6. We also know that d = 2f - 3 from the last sentence. Line up and simplify the equations:

d + 3 = 3e + 9, or d = 3e + 6 -----> e + 3 = f - 3 ------> d = 2f - 3

Since the first and third equations are set equal to d, combine them: 3e + 6 = 2f - 3

Now there are two equations, each of which has the same two variables, e and f: e + 3 = f - 3, or e = f - 6 ----> 3e + 6 = 2f - 3

Substitute the value of e from the first equation into the second: 
3(f - 6) + 6 = 2f - 3 ----> 3f - 18 + 6 = 2f - 3 -----> 3f - 9 = 2f -----> f = 9, choice (A).

Hope it helps

PareshGmat · Answer

Let the present ages of Dathan, Ellen & Famke be d , e & f

So from the information given in the question, we get the following 3 equations:

d+3 = 3(e+3)
e = f-6
d = 2f - 3

Solving the above 3 equations, we get Famke = 9 yrs = Answer = A

mvictor · Answer

D+3=3(E+3)
E+3=(F+3)-6
D=2F-3.

E+3=F-3 or E=F-6.
D+3=3(F-6+3) 
D+3=3F-9
D=3F-12.
now, we have D=2F-3.

2F-3=3F-12
9=F.

F=9. A.

KarishmaB · Answer

We need to find Famke's age so say it is F.

Then Dathan's age = 2F - 3
Ellen's age = F - 6 (If in 3 yrs, Ellen will be 6 yrs younger than Famke, she must be 6 yrs younger today too)
Dathan + 3 = 3(F - 6 + 3)

So 
2F - 3 = 3(F - 3) - 3 
F = 9 yrs

Answer (A)

KanishkM · Answer

So whats given, x = Dathan, y = Ellen & z = Famke

x + 3 = 3y + 9

y + 3 = z - 3

x = 2z - 3

Now just manipulate above expressions to get

2z - 3y = 9 ----------(b)
z - y = 6------------(a)

Multiply (a) by 2 and then subtract from (b)
y = 3

z = 9

A

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Three years from now, Dathan will be three times as old as E

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