Alice is twice as old as Brian and Cathy is 6 years younger than Brian

Question

Alice is twice as old as Brian and Cathy is 6 years younger than Brian. If Alice is a years old, how old is Cathy in terms of a ?

A. a + 6
B. a − 6
C. (a - 12)/2
D. (a + 12)/2
E. 2a − 6

KSBGC · Answer

a=20 years.

A= 20.

B = 10

C = 16.

Option D matches.

Put the value in to the equation.

Archit3110 · Answer

Alice is twice as old as Brian and Cathy is 6 years younger than Brian. If Alice is a years old, how old is Cathy in terms of a ?

A. a + 6
B. a − 6
C. (a - 12)/2
D. (a + 12)/2
E. 2a − 6

Given relation: A=2b
 selim  : C is younger than b so eqn should be C=B-6

solve for C we get C= (a-12)/2
option C should be correct..

BrentGMATPrepNow · Answer

GIVEN: Alice is  a  years old

Alice is twice as old as Brian  
This also means Brian is HALF as old as Alice
So, Brian's age =  a /2

Cathy is 6 years younger than Brian  
So, Cathy's age = (Brian's age) - 6
So, Cathy's age = ( a /2) - 6

How old is Cathy in terms of a ?  
Cathy's age = ( a /2) - 6
=  a /2 - 12/2
= (a - 12)/2

Answer: C

Cheers,
Brent

Abhishek009 · Answer

Break down and solve a = 2b c = b - 6

So, We can say :  c = \frac{a}{2} - 6  ie,  \frac{(a - 12)}{2}

Answer must be (C)

Nighat Bano · Answer

a = 2b ==> b = a/2
c = b-6 ==> c = (a/2) - 6 ==> c = (a-12) / 2 ---- ANSWER = C

ScottTargetTestPrep · Answer

We are given that a = Alice’s current age, and we can let b = Brian’s current age and c = Cathy’s current age and create the equations:

a = 2b

and

c = b - 6

c + 6 = b

Substituting, we have:

a = 2(c + 6)

a = 2c + 12

a - 12 = 2c

(a - 12)/2 = c

Answer: C

Slicerad · Answer

Make B=X, so
A=2X
C=X-6

Make a=2X, so X=a/2.

C=(a/2)-6 = (a-12)/2

Posted from my mobile device

bumpbot · Answer

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Alice is twice as old as Brian and Cathy is 6 years younger than Brian

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Alice is twice as old as Brian and Cathy is 6 years younger than Brian

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