Roy is now 4 years older than Erik and half of that amount

Question

Roy is now 4 years older than Erik and half of that amount older than Iris. If in 2 years, Roy will be twice as old as Erik, then in 2 years what would be Roy’s age multiplied by Iris’s age?

(a) 8
(b) 28
(c) 48
(d) 50
(e) 52

Bunuel · Accepted Answer

Roy is now 4 years older than Erik -->  R=E+4 
Roy is now ... half of that amount older than Iris -->  R=I+\frac{4}{2}=I+2  (half of the amount of 4)
In 2 years, Roy will be twice as old as Erik -->  R+2=2(E+2)  (in 2 years for both Roy and Eric)

Then in 2 years what would be Roy’s age multiplied by Iris’s age -->  (R+2)(I+2)=?

Solving:  R=6  and  I=4  -->  (R+2)(I+2)=48

Answer: C.

PareshGmat · Answer

Roy .............. Erik ............ Iris

x+4 ................ x .................. x+2 .................. Current Ages

(Roy 4 yrs older than Erik & 2 yrs older than Iris)

Ages after 2 yrs

x+6 ................ x+2 .................. x+4

x+6 = 2(x+2) ........ Roy is twice the age of Erik

x = 2

Roy * Iris = 8 * 6 = 48

Answer = C

chix475ntu · Answer

r=e+4 -- 1st 
4=i+2 .. 2nd

in 2 years 
r+ 2 = 2 * (I+2) .. 3rd

solving 1st and 3rd equation we get r=6, i = 2, and using 2nd equation we get i=4

so in 2 years r=8 and i=6, product =48

C

AtifS · Answer

Hmm! would you please! explain a bit how did u get 2nd & 3rd equations?
as if I take "If in 2 years, Roy will be twice as old as Erik" the n it means that
r+2=2e -- 2nd

and I didn't get these words "and half of that amount older than Iris" plzz! explain it.

Any help would be highly appreciated.

AtifS · Answer

Thanks for explanation, Actually i couldn't get the equation with  I  otherwise I had solved other equations instead of this one

R=I+\frac{4}{2}=I+2  (half of the amount of 4)

looks like have to work on Word Problems.
thanks again and Kudos
couldn't get this part  (half of the amount of 4)

Dienekes · Answer

I did this with back-solving and fortunately struck gold in the first attempt itself, i.e. testing with C.

TeamGMATIFY · Answer

Since we have been given everything in terms of the of Erik, Let us assume the age of Erik to be E And, the term " half of that amount" refers to the value 4. Erik age.JPG E + 6 = 2E + 4 E = 2 Therefore, (Roy's age)* (Iris's age) = 8*6 = 48 Option C

seemachandran · Answer

Folks

Please help me understand;

interpreted the Q stem incorrectly

Roy is now 4 years older than Erik and half of that amount older than Iris. If in 2 years, Roy will be twice as old as Erik, then in 2 years what would be Roy’s age multiplied by Iris’s age

'half of that amount' -- I interpreted as r= i+ 1/2(e+4)

How do i know half of that amount means - half of '4 years older'

law258 · Answer

We can derive the following equations:

R=4+E --> (2 years later) --> R+2=2(E+2) solves to give E=2 & R=6 --> (2 years down the road) --> R = 8
R=2+I --> I = 4 -->(2 years later) --> I=6

6x8 = 48

longhaul123 · Answer

this is my method of solving . Can someone correct me in which step am i going wrong ?
So the first equation is R=4+E
So R is half of that amount older than I. So why cant the equation be 4+E/2 +I
whats wrong in this formulation of the statement??
So in this case R +2 = 8 and I+2= 5 
So the answer is 40

masoomjnegi · Answer

Translate piece by piece into numbers. 
R (Rehana) = Erik (E) + 4.
The second equation: R = I (Iris) + 2.
The third equation: R +7 = 2(E + 7). 
We have three equations with three variables.
 Rehana is 6, Iris is 4 and Erik is 2. 
In four years Erik would be 6 and Iris 8, 
the answer is 48.

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Roy is now 4 years older than Erik and half of that amount

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Roy is now 4 years older than Erik and half of that amount

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