SOLUTION: The age difference between two brothers is 3 years. After 6 years the ratio between the age is 9:8 What are their ages?

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Question 579482: The age difference between two brothers is 3 years. After 6 years the ratio between the age is 9:8
What are their ages?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +a+ = the age of the younger brother now
+a+%2B+3+ = the age of the older brother now
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given:
In 6 years:
+a+%2B+6+ = the age of the younger brother
+a+%2B+3+%2B+6+ = the age of the older brother
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+%28+a+%2B+9+%29+%2F+%28+a+%2B+6+%29+=+9%2F8+
Multiply both sides by +8%2A%28+a+%2B+6+%29+
+8%2A%28+a+%2B+9+%29+=+9%2A%28+a+%2B+6+%29+
+8a+%2B+72+=+9a+%2B+54+
+a+=+72+-+54+
+a+=+18+
+a+%2B+3+=+21+
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The older brother is 21 now
The younger brother is 18 now
check:
+%28+a+%2B+9+%29+%2F+%28+a+%2B+6+%29+=+9%2F8+
+%28+18+%2B+9+%29+%2F+%28+18+%2B+6+%29+=+9%2F8+
+27+%2F+24+=+9%2F8+
Multiply both sides by +8%2A24+
+8%2A27+=+24%2A9+
+216+=+216+
OK