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rjkz [21]
2 years ago
10

If (n+1)!=90×(n-1)!,find n.​

Mathematics
1 answer:
Helen [10]2 years ago
4 0

 

\displaystyle\bf\\(n+1)!=90\times (n-1)!\\\\(n-1)!\times n\times(n+1)=90\times (n-1)!~~~\Big|~:(n-1)!\\\\n(n+1)=90\\\\n(n+1)=9\times10\\\\n(n+1)=9(9+1)\\\\\implies~~\boxed{\bf n=9}

 

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Answer:

Step-by-step explanation:

Given the expressions :

The list price of the item is 80 percent of the original price. The price of the item has been reduced by 80 percent.

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Expression 2: The price of the item has been reduced by 80 percent

Price = x - 80% of x

Price = x - 0.8x

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Multiply by percentages is different from an Incremental or decrement in percentage. The first expression above signifies a direct multiplication by the stated percentage while the second signifies a decrease in price based on a certain percentage of the original price.

Wording of percentages are so important for clarity in other to understand if the statement signifies a direct application of the percentage prescribed or a change in quantity, amount or size relative to the base unit.

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Step-by-step explanation:

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Step-by-step explanation:

<em>Difference</em><em> </em><em>=</em><em>$</em><em>(</em><em>3</em><em>0</em><em>3</em><em>-</em><em>1</em><em>9</em><em>4</em><em>)</em>

<em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em> </em><em>=</em><em>$</em><em>1</em><em>0</em><em>9</em>

<em>Hope</em><em> </em><em>this</em><em> </em><em>helps</em>

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