\"\"

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According to Means-extremes Property of proportion: If \"\", then ad = bc.

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\"\"                        (Cross products)

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\"\"

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\"\"                              (Multiply: \"\")

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\"\"                        (Divide each side by 15)

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\"\"                               (Cancel common terms) \ \

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\"\"                                     (Divide: \"\")

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\"\"

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The value of a =225.

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