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3 years ago

Does anyone know the answer to this and how to solve it? I’m completely lost-

Mathematics

1 answer:

vovangra [49]3 years ago

7 0

Answer:

314

Step-by-step explanation:

Does the line cuts through the diameter of the circle?

If so just apply π * 10^2 = 314.15 radius is just 20/2 = 10

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Write the sum of the numbers as the product of their GCF and another sum.

8090 [49]

Answer:

See explanation

Step-by-step explanation:

1. Find the GCF of 40 and 44:

$40=\underline{2\cdot 2}\cdot 2\cdot 5\\ \\44=\underline{2\cdot 2}\cdot 2\cdot 11\\ \\GCF(40,44)=2\cdot 2=4$

So,

$40+44=4\cdot 10+4\cdot 11=4\cdot (10+11)$

2. Find the GCF of 13 and 52:

$13=\underline{13}\\ \\52=2\cdot 2\cdot \underline{13}\\ \\GCF(13,52)=13$

So,

$13+52=13\cdot 1+13\cdot 4=13\cdot (1+4)$

3. Find the GCF of 15 and 81:

$15=\underline{3}\cdot 5\\ \\81=\underline{3}\cdot 3\cdot 3\cdot 3\\ \\GCF(15,81)=3$

So,

$15+81=3\cdot 5+3\cdot 27=3\cdot (5+27)$

4. Find the GCF of 64 and 28:

$64=\underline{2\cdot 2}\cdot 2\cdot 2\cdot 2\cdot 2\\ \\28=\underline{2\cdot 2}\cdot 7\\ \\GCF(64,28)=2\cdot 2=4$

So,

$64+28=4\cdot 16+4\cdot 7=4\cdot (16+7)$

6 0

3 years ago

You have $75.00 to spend at the mall. You want to buy a hoodie that costs $80.00. The store is having a 20%-off sale. (There is

lesya692 [45]

Ok so find 20% off and see if less tha 75
percent means parts out of 100
20% means 20/100=1/5

'of' means multiply

20% of 80=1/5 times 80=16

off means subtract
disctoun tof 16 is 80-16=64
64<75

how much left over
75-spent=left over
75-64=11

anwwer is $11 left over and enough money to buy

6 0

3 years ago

Read 2 more answers

use the general slicing method to find the volume of The solid whose base is the triangle with vertices (0 comma 0 ), (15 comma

lyudmila [28]

Answer:

volume V of the solid

$\boxed{V=\displaystyle\frac{125\pi}{12}}$

Step-by-step explanation:

The situation is depicted in the picture attached

(see picture)

First, we divide the segment [0, 5] on the X-axis into n equal parts of length 5/n each

[0, 5/n], [5/n, 2(5/n)], [2(5/n), 3(5/n)],..., [(n-1)(5/n), 5]

Now, we slice our solid into n slices.

Each slice is a quarter of cylinder 5/n thick and has a radius of

-k(5/n) + 5 for each k = 1,2,..., n (see picture)

So the volume of each slice is

$\displaystyle\frac{\pi(-k(5/n) + 5 )^2*(5/n)}{4}$

for k=1,2,..., n

We then add up the volumes of all these slices

$\displaystyle\frac{\pi(-(5/n) + 5 )^2*(5/n)}{4}+\displaystyle\frac{\pi(-2(5/n) + 5 )^2*(5/n)}{4}+...+\displaystyle\frac{\pi(-n(5/n) + 5 )^2*(5/n)}{4}$

Notice that the last term of the sum vanishes. After making up the expression a little, we get

$\displaystyle\frac{5\pi}{4n}\left[(-(5/n)+5)^2+(-2(5/n)+5)^2+...+(-(n-1)(5/n)+5)^2\right]=\\\\\displaystyle\frac{5\pi}{4n}\displaystyle\sum_{k=1}^{n-1}(-k(5/n)+5)^2$

But

$\displaystyle\frac{5\pi}{4n}\displaystyle\sum_{k=1}^{n-1}(-k(5/n)+5)^2=\displaystyle\frac{5\pi}{4n}\displaystyle\sum_{k=1}^{n-1}((5/n)^2k^2-(50/n)k+25)=\\\\\displaystyle\frac{5\pi}{4n}\left((5/n)^2\displaystyle\sum_{k=1}^{n-1}k^2-(50/n)\displaystyle\sum_{k=1}^{n-1}k+25(n-1)\right)$

we also know that

$\displaystyle\sum_{k=1}^{n-1}k^2=\displaystyle\frac{n(n-1)(2n-1)}{6}$

and

$\displaystyle\sum_{k=1}^{n-1}k=\displaystyle\frac{n(n-1)}{2}$

so we have, after replacing and simplifying, the sum of the slices equals

$\displaystyle\frac{5\pi}{4n}\left((5/n)^2\displaystyle\sum_{k=1}^{n-1}k^2-(50/n)\displaystyle\sum_{k=1}^{n-1}k+25(n-1)\right)=\\\\=\displaystyle\frac{5\pi}{4n}\left(\displaystyle\frac{25}{n^2}.\displaystyle\frac{n(n-1)(2n-1)}{6}-\displaystyle\frac{50}{n}.\displaystyle\frac{n(n-1)}{2}+25(n-1)\right)=\\\\=\displaystyle\frac{125\pi}{24}.\displaystyle\frac{n(n-1)(2n-1)}{n^3}$

Now we take the limit when n tends to infinite (the slices get thinner and thinner)

$\displaystyle\frac{125\pi}{24}\displaystyle\lim_{n \rightarrow \infty}\displaystyle\frac{n(n-1)(2n-1)}{n^3}=\displaystyle\frac{125\pi}{24}\displaystyle\lim_{n \rightarrow \infty}(2-3/n+1/n^2)=\\\\=\displaystyle\frac{125\pi}{24}.2=\displaystyle\frac{125\pi}{12}$