The summation symbol means we use the variable i in the equation from the given range. In this case, we are given with the equation 3 i - 15 and i ranges from 2 to 7. The summation using simply the calculator is equal to -9. The answer to this problem is -9.

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3 years ago

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Write the ratio of the area of a circle with radius r to the circumference of the same circle

Goshia [24]

Answer:

$\frac{r}{2\pi r} =\frac{1}{2\pi }$

Step-by-step explanation:

A ratio is a comparison of two quantities and can be written in several forms including fractions. It is most commonly written in fraction form or a:b.

To write a ratio, we count the number of each quantity we are comparing or use the variable for that quantity. We write radius:circumference. Recall, the circumference of a circle can be found using $\pi d$ or $2\pi r$ .

We write r: $\pi d$ or r: $2\pi r$ .

We can also write in fraction form:

$\frac{r}{\pi d}$ or $\frac{r}{2\pi r} =\frac{1}{2\pi }$

6 0

3 years ago