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" id="TexFormula1" title=" \frac{4 }{4 - x} = \frac{5}{(4 + x)} " alt=" \frac{4 }{4 - x} = \frac{5}{(4 + x)} " align="absmiddle" class="latex-formula">
for X

Mathematics

1 answer:

lisov135 [29]3 years ago

6 0

$Domain:\\4-x\neq0\ \wedge\ 4+x\neq0\\x\neq4\ \wedge\ x\neq-4\\\\\dfrac{4}{4-x}=\dfrac{5}{4+x}\qquad\text{cross multiply}\\\\4(4+x)=5(4-x)\qquad\text{use distributive property}\\\\(4)(4)+(4)(x)=(5)(4)+(5)(-x)\\\\16+4x=20-5x\qquad\text{subtract 16 from both sides}\\\\4x=4-5x\qquad\text{add 5x to both sides}\\\\9x=4\qquad\text{divide both sides by 9}\\\\\boxed{x=\dfrac{4}{9}}$

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In a company 60% of the workers are men is 880 women work for the company how many workers are there in all

borishaifa [10]

I will do my best to answer this question due to the gramatical errors made making it difficult to read and understand.
assuming that the 880 is the number of women employed that makes up 40% of the company employees
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7 0

3 years ago

Find the sum of the geometric series 40 + 40(1.005) + 40(1.005)^2 + ⋯ + 40(1.005)^11.

KiRa [710]

Answer:

The sum is 493.4

Step-by-step explanation:

In order to find the value of the sum, you have to apply the geometric series formula, which is:

$\sum_{i=1}^{n} ar^{i-1} = \frac{a(1-r^{n})}{1-r}$

where i is the starting point, n is the number of terms, a is the first term and r is the common ratio.

The finite geometric series converges to the expression in the right side of the equation. Therefore, you don't need to calculate all the terms. You can use the expression directly.

In this case:

a=40

b= 1.005

n=12 (because the first term is 40 and the last term is 40(1.005)^11 )

Replacing in the formula:

$\frac{a(1-r^{n})}{1-r} = \frac{40(1-1.005^{12})}{1-1.005}$