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Question
Find the fourth proportional to 3a, 6a2 and 2ab2
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Solution
Let the fourth proportional to 3a, 6a2 and 2ab2 be x.
`\implies` 3a : 6a2 = 2ab2 : x
`\implies` 3a × x = 2ab2 × 6a2
`\implies` 3a × x = 12a3b2
`\implies` x = 4a2b2
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