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4 years ago

What is the value of ?A. 7.5 B. 17.5 C. 60.5 D. 76.5

Mathematics

2 answers:

REY [17]4 years ago

8 0

Answer:

76.5

Step-by-step explanation:

Recall that for any positive integer n

n! = 1*2*3*4*...*n

For example

5! = 1*2*3*4*5 = 120

$\sum_{n=2}^6\frac{(n-1)!}{2}=\frac{(2-1)!}{2}+\frac{(3-1)!}{2}+\frac{(4-1)!}{2}+\frac{(5-1)!}{2}+\frac{(6-1)!}{2}=\\\\=\frac{1!}{2}+\frac{2!}{2}+\frac{3!}{2}+\frac{4!}{2}+\frac{5!}{2}=\frac{1}{2}+\frac{1*2}{2}+\frac{1*2*3}{2}+\frac{1*2*3*4}{2}+\frac{1*2*3*4*5}{2}=\\\\=\frac{1}{2}+1+3+12+60=\boxed{76.5}$

Marina CMI [18]4 years ago

7 0

Answer:

D on edge

Step-by-step explanation:

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3 years ago

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Answer:

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3 years ago

A rectangle has an area of 171 square meters. Its width is ten meters less than the length. Find the measures of the length and

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Step-by-step explanation:

The area of a rectangle is 171 m²

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b = l-10 ...(1)

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b = 19-10 = 9 m

So, the length an the breadth of the rectangle is 19 m and 9 m respectively.

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3 years ago