SOLUTION: A boy is twice as old as his younger brother, and half as old as his older brother. In 22 years, his younger brother will be half as old as his oldr brother. What are the three boy

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Question 1107736: A boy is twice as old as his younger brother, and half as old as his older brother. In 22 years, his younger brother will be half as old as his oldr brother. What are the three boy's current ages?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +a+ = his younger brother's age
Let +b+ = his age
Let +c+ = his older brother's age
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(1) +b+=+2a+
(2) +b+=+%281%2F2%29%2Ac+
(3) +a+%2B+22+=+%281%2F2%29%2A%28+c+%2B+22+%29+
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(2) +c+=+2b+
and
(1) +a+=+%281%2F2%29%2Ab+
Plug these results into (3)
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(3) +%281%2F2%29%2Ab+%2B+22+=+%281%2F2%29%2A%28+2b+%2B+22+%29+
Multiply both sides by +2+
(3) +b+%2B+44+=+2b+%2B+22+
(3) +b+=+22+
and
(1) +a+=+%281%2F2%29%2Ab+
(1) +a+=+%281%2F2%29%2A22+
(1) +a+=+11+
and
(2) +c+=+2b+
(2) +c+=+2%2A22+
(2) +c+=+44+
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The younger brother is 11
He is 22
The older brother is 44
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