In 10 years Linda will be as old as Bobby is now. Thirty years ago Bob

Question

In 10 years Linda will be as old as Bobby is now. Thirty years ago Bobby was twice Linda's age. How old is Linda now?

A. 20
B. 30
C. 40
D. 50
E. 60

Harshit401 · Answer

Am I Correct?

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Bunuel · Answer

The OA will be automatically revealed on Monday 30th of January 2017 08:45:39 AM Pacific Time Zone.

P.S. Please post a solution instead of single letter replies.

dave13 · Answer

Here is my solution: L = B+10 B = 30-2(B+10) L= 30-2(B+10)+10 L= 30-2B-20+10 2B= 20 B = 10 Linda = 10+10 = 20 Is it A ? please correct me if i am wrong

thanks

Shashank1988 · Answer

Lets say Linda is 40 now ( Taken option C )
In 10 years Linda will be as old as Bobby is now : So in 10 years Linda will be 40+10= 50 years , so Bobby's age is 50 years now .

Thirty years ago Bobby was twice Linda's age : So Thirty years ago Linda's age was 40-30= 10 and Bobby's age 50-30 = 20 years . 
Therefore we can see Bobby's age is twice as Linda's age .

BillyZ · Answer

Linda + 10 = Bobby - (1) 
 Bobby - 30 = 2 (Linda - 30) - (2)

Substitute equation (1) into (2)

Linda + 10 - 30 = 2 Linda - 60 
 Linda = 60 + 10 - 30 
 Linda = 40

Answer : C. 40

laddaboy · Answer

The first equation is l+10 = b
The second equation is b-30 = 2(l-30) . Hence L = 40 Option C

chetan2u · Answer

Apart from the checking choices and proper method, another logical way to look at the Q..

In 10 years Linda will be as old as Bobby is now. MEANS   difference in age is 10 .

Thirty years ago Bobby was twice Linda's age. 
 if the difference is 10, doubling can be ONLY when the younger is EQUAL to this difference, 10 
If I have to make an equation..
Age of younger is x, so age of elder will be x+10..
Now 2x=(x+10)... x=10..
Present age =30+10=40..

NNDD · Answer

<== 30 years------Now----10 years==>

I will eliminate answer A & B ...if she is 20 or 30 years now, then she wasn't born yet 30 years ago.

by trying answer choice (c)

L+10=B (1) ==> 40+10 =50
B=50 from (1) (now)

B-30=2(L-30) ==> 50-30 = 2(40-30)

which means...30 years ago B was 20 and L was 10

Answer is C (40)

dave13 · Answer

i got it, many thanks for taking time to correct me - laddaboy

ScottTargetTestPrep · Answer

We can let L = Linda’s age today and B = Bobby’s age today.

We are given that in 10 years Linda will be as old as Bobby is now. Thus:

10 + L = B

We are also given that thirty years ago Bobby was twice Linda's age, thus:

B - 30 = 2(L - 30)

B - 30 = 2L - 60

B = 2L - 30

Since B = 2L - 30, we can substitute 2L - 30 for B in the equation 10 + L = B and we have:

10 + L = 2L - 30

40 = L

Answer: C

bumpbot · Answer

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In 10 years Linda will be as old as Bobby is now. Thirty years ago Bob

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