SOLUTION: my brother is two years younger than me. If I gave my sister two years she would be twice my age and if my sister gave my brother one year they would both the same age. How old is

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Question 762239: my brother is two years younger than me. If I gave my sister two years she would be twice my age and if my sister gave my brother one year they would both the same age. How old is each of us?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +m+ = my age
Let +b+ = brother's age
Let +s+ = sister's age
---------------------
Note that if I give my sister 2 years, I become +m+-+2+
and she becomes +s+%2B+2+
Also, if my sister gives brother 1 year, she becomes +s+-+1+
and he becomes +b+%2B+1+
given:
(1) +b+=+m+-+2+
(2) +s+%2B+2+=+2%2A%28+m+-+2+%29+
(3) +s+-+1+=+b+%2B+1+
-------------------
(3) +b+=+s+-+2+
Plug this into (1)
(1) +s+-+2+=+m+-+2+
(1) +s+=+m+
Plug this into (2)
(2) +m+%2B+2+=+2%2A%28+m+-+2+%29+
(2) +m+%2B+2+=+2m+-+4+
(2) +m+=+6+
and, since
(1) +s+=+m+
(1) +s+=+6+
also,
(3) +b+=+s+-+2+
(3) +b+=+4+
--------------
check:
My brother is two years younger than me.
OK
If I gave my sister two years she would be twice my age
+s+%2B+2+=+8+
+m+-+2+=+4+
OK
if my sister gave my brother one year they would both the same age
+6+-+1+=+5+
+4+%2B+1+=+5+
OK