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3 years ago

PLEASE HELP ASAP!!! CORRECT ANSWER ONLY PLEASE!!!

Mathematics

2 answers:

Vinvika [58]3 years ago

6 0

Hello there,

What is the sum of the first 7 terms of the series −8 +16 −32 + 64−... ?

Answer: -258

ch4aika [34]3 years ago

3 0

Answer: -258

Step-by-step explanation:

Given the sequence {-8, 16, -32, 64, ... , a₇} we know the following

the first term (a₁) = -8
the common ratio (r) = -2
the number of terms (n) = 7

Input the information above into the Sum formula:

$S_n=\dfrac{a_1(1-r^n)}{1-r}\\\\S_7=\dfrac{-8(1-(-2)^7)}{1-(-2)}\\\\.\quad =\dfrac{-8(1-(-128))}{1+3}\\\\.\quad =\dfrac{-8(129)}{4}\\\\.\quad =-2(129)\\\\.\quad =-258$

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A fulcrum moving a resistance of 200 g has a distance to the fulcrum of 20 cm, the effort mass of 50 g has a distance to the ful

S_A_V [24]

Answer:

The ideal mechanical advantage (IMA) is $4$ .

Step-by-step explanation:

The ideal mechanical advantage is the ratio of length of longer lever $L_e$ to that of shorter lever $L_r$

IMA $\frac{L_e}{L_r}$

Please refer to the image attached.

We could see that the the resistance load moves $10\ cm$ cm towards the fulcrum so the distance of resistance load from fulcrum $= (20-10) =10\ cm$

Now the as the effort force moves $40\ cm$ towards the fulcrum overall distance from the fulcrum to the effort force (load) $=(80-40)=40\ cm$

Plugging the values of the distances in IMA formula we can have.

IMA $=\frac{(80-40)}{(20-10)} =\frac{40}{10} =4$ .

So the IMA of the fulcrum (simple machine) $= 4$

3 0

4 years ago

Write an expression using distributive property that can be used to find the quotient 56 divided by 4

kicyunya [14]

(50/4) + (6/4) is the answer that you are looking for. All you do is break up the number that you are going to divide into easy-to-divide numbers.

4 0

3 years ago

Whats the answer and an explanation

Dmitry [639]

N=4
Remove the parentheses, move the terms, collect like terms,calculate, divide both sides

4 0

3 years ago

Read 2 more answers

How much does a glass cube with a side of 5-cm weigh if 1cm3 of glass weighs 2 2/5 grams?

PtichkaEL [24]

The weight of galss cube with side 5 cm is 300 grams

Solution:

A glass cube is of side length 5 cm

Let us first find the volume of glass cube

The volume of cube is given as:

$volume = (side)^3\\\\volume =5^3 = 125$

Thus volume of cube is 125 $cm^3$

Given that,

$1 cm^3 = 2\frac{2}{5} \text{ grams }\\\\1 cm^3 =\frac{12}{5} \text{ grams}$

So, weight of 125 cubic centimeter of glass cube is found by multiplying weight of 1 cubic centimeter of glass cube by 125

$\text{ Weight of 125 } cm^3 \text{ cube } = \text{ Weight of 1 } cm^3 \text{ cube } \times 125$

$\text{ Weight of 125 } cm^3 \text{ cube } = \frac{12}{5} \times 125 = 25 \times 12 = 300$

Thus weight of galss cube with side 5 cm is 300 grams

3 0

3 years ago

Read 2 more answers

An engineer is planning a new water pipe installation. The circular pipe has a diameter of d=20\text{ cm}d=20 cmd, equals, 20, s

aivan3 [116]

Answer: The answer is 314.28 cm² (approx.).

Step-by-step explanation: Given that an engineer is going to install a new water pipe. The diameter of this circular pipe is, d = 20 cm.

We need to find the area 'A' of the circular cross-section of the pipe.

Given, diameter of the circular section is

$\textup{d}=20~\textup{cm}.$

So, the radius of the circular cross-section will be

$\textup{r}=\dfrac{\textup{d}}{2}=\dfrac{20}{2}=10~\textup{cm}.$

Therefore, cross-sectional area of the pipe is

$\textup{A}=\pi \textup{r}^2=\dfrac{22}{7}(10)^2=\dfrac{2200}{7}=314\dfrac{2}{7}=314.28~.~.~.~\textup{cm}^2.$

Thus, the answer is 314.28 cm² (approx.).

4 0

4 years ago