$\"\"$

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A paino has $\"\"$ white keys,write and use an equation to find the number of octaves on a paino keyboard.

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Find an equation.

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Let $\"\"$ represents number of a paino keyboard.

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The number of octaves on a paino keyboards is $\"\"$ .

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A paino has $\"\"$ white keys.

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His has total white keys is equal to the number of octaves on a paino keyboards.

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The equation is $\"\"$ .

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Fifty equal eight times of $\"\"$ .

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$\"\"$

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$\"\"$

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Find the number of paino keyboard.

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$\"\"$ (Orginal equation)

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$\"\"$ (Divide each side by $\"\"$ )

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$\"\"$ (Cancel common terms)

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Therefore, the number of octaves on a $\"\"$ paino keyboards.

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$\"\"$

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Check :

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$\"\"$ (Orginal equation)

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$\"\"$ (Substitute $\"\"$ in the equation)

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$\"\"$ (Multiply)

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$\"\"$

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The equation is $\"\"$ .

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The number of octaves on a paino keyboards is $\"\"$ .