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3 years ago

I need help please????

Mathematics

1 answer:

ivanzaharov [21]3 years ago

3 0

-84
21x4=84 plus the negative

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At a large regional collegiate women’s swim meet, an official records the time it takes each swimmer to swim 100 meters for all

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Answer:

1.6726

Step-by-step explanation:

square each standard deviation, add them then squareroot.

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2 years ago

6. A tank contains 100-gallon of pure water. At time t = 0, a solution containing 2 lb of salt per gallon flows into the tank at

SOVA2 [1]

Answer:

The answer is below

Step-by-step explanation:

Let Q represent the amount of salt in the tank at time t.

$\frac{dQ}{dt}= flow\ in - flow\ out\\ \\flow\ in=3\ gal/min*2\ lb/gal=6\ lb/min\\\\net\ gain\ in\ tank\ volume=3-4=-1, henceflow\ out= \frac{4Q}{100-t} \\\\\frac{dQ}{dt}= 6-\frac{4Q}{100-t} \\\\\frac{dQ}{dt}+ \frac{4Q}{100-t}=6\\\\The \ integrating\ factor\ is:\\\\IF=e^{\int\limits {\frac{4}{100-t} } \, dt }=e^{-4\int\limits {\frac{-1}{100-t}}=e^{-4ln(100-t)}=(100-t)^{-4}}\\\\Multiplying\ through \ by\ IF: \\\\(100-t)^{-4}\frac{dQ}{dt}+ (100-t)^{-4}\frac{4Q}{100-t}=6(100-t)^{-4}\\\\$

$Integrating:\\\\A(100-t)^{-4}=-2(100-t)^{-3}+c\\\\A=-2(100-t)+\frac{c}{(100-t)^{-4}} \\\\at, t=0,A=0\\\\0=-2(100-0)+\frac{c}{(100-0)^{-4}}\\\\c=0.02\\\\A=-2(100-t)+\frac{0.02}{(100-t)^{-4}}$

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2 years ago

Y=3x\4 if y= -6 find the value of x<br>please answer this for me, it's graded

sveticcg [70]

Answer:

x = -8

Step-by-step explanation:

y = 3x/4

Substitute the value of -6 into y.

-6 = 3x/4

Multiply both sides by 4.

-24 = 3x

Divide both sides by 3.

x = -8.

4 0

2 years ago

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A suitcase measures 24 inches long and the dialogue is 30 inches long. How much material is needed to cover one side of the suit

borishaifa [10]

Answer:

432 in.^2

Step-by-step explanation:

The side of the suitcase is a rectangle. One length is 24 inches. The diagonal of the rectangle is 30 inches long. The diagonal is a hypotenuse of a right triangle. The length is a leg. We need to find the other leg.

We use the Pythagorean theorem,

a^2 + b^2 = c^2

(24 in.)^2 + b^2 = (30 in.)^2

576 in.^2 + b^2 = 900 in.^2

b^2 = 324 in.^2

b = sqrt(324 in^2)

b = 18 in

area of rectangle = length * width

A = 24 in. * 18 in.

A = 432 in.^2

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3 years ago

If you take Coleman's test grade and divide by 2 and add 27, you get 67. Write and solve an equation to find Coleman's test grad

alekssr [168]

It's c because. 80 divided. by 2 equals 40 then add 27 that equals 67

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2 years ago

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