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Alison is currently twice as old as Mike. 4 years ago, Alison was three times as old as Mike. How old is Alison now?

 Mar 30, 2020
 #1
avatar+663 
+1

Was 11 minutes quick enough?

 

Alison is twice as old as mike.

[1] A = 2M

 

4 years ago, Alison was three times as old as Mike.

[2] (A - 4) = 3(M-3)

 

Substitute [1] and [2]

1. (2M - 4) = 3(M-3)

2. 2M - 4 = 3M - 9

3. M = 5

 

Now how old is Alison? (Hint: Substitute M back in [1])

 Mar 30, 2020
 #2
avatar+112277 
+1

Let Mike's current  age  = M  and Alison's =  2M

 

4 years ago we  had that

 

2M - 4  =   3 (M - 4)      simplify

 

2M - 4  =  3M  - 12      add  12 to both sides, subtract 2M from both sides

 

8  = M

 

2M  =  16  = Alison's age now

 

cool cool cool

 Mar 30, 2020

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