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3 years ago

Help Me with theses four questions please ty

Mathematics

2 answers:

Alex_Xolod [135]3 years ago

5 0

1. 135.4896pi m^2
2. 39.69pi cm^2
3.1017 mm^2
4.225pi cm^2

The formula for these problems is

kondor19780726 [428]3 years ago

4 0

1. 135.4896pi m^2
2. 39.69pi cm^2
3.1017 mm^2
4.225pi cm^2

The formula for these problems is $A= \pi r^{2}$

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Please help i am super confused and it is worth a lot of points !!!! Find the measure of

garri49 [273]

Answer:

its probably around 110* or 100

Step-by-step explanation:

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2 years ago

Neil is buying steak for a cookout on Saturday. Steak is on sale for $9.62 per pound. If he buys 7.5 pounds of steak, how much m

Ad libitum [116K]

Answer:

$72.15

Step-by-step explanation:

x= pounds of steak

$ $9.62x$ = money spent on steaks

If Neil buys 7.5 pounds of steak then x =7.5

$9.62(7.5) = $72.15

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3 years ago

Read 2 more answers

Find the exact length of the arc s in the figure. (Assume r = 3 and θ = 106°.)

NemiM [27]

Circumference = 2Pi(r) = 6Pi

angle of arc s = 360 - 106 = 254 degree

Arc length = 6Pi ( 254 ) / 360 = 4.2Pi

Pi = 3.14

8 0

3 years ago

Eric is comparing the credit scores of his friends. The scores he gathered are found in the table below. 588 838 691 818 846 725

alukav5142 [94]

To solve this, we need to know how to find the mean of a set of data and how to find the median of a set of data.

To find the mean, or often called the average, we should add all of the values up, and then divide it by the number of values.

588+838+691+818+846+725+605+732+750 = 6593
6593/9=732.556

The problem tells us we should round to the nearest point, so our mean credit score is 733.

To find the median, we need to order the data from lowest to highest and find out which credit score(s) are right in the middle. If there are 2 in the middle, we simply should add them and divide by 2 to get our median. An easy way to do this is after you order them, you simply cross off one on each side until there is only 1 (or 2) left.

588 605 691 725 732 750 818 838 846
605 691 725 732 750 818 838
691 725 732 750 818
725 732 750
732

Since we only have one number in the middle, we are done with the median! We know our median is 732.

Now we simply need to compare them and subtract the lower one from the higher one.

Mean:733
Median: 732
733>732

We know the mean is bigger, so we should subtract the median from the mean.

733=732=1

Using the logic above, we can see that the mean is 1 point higher than the median.

8 0

3 years ago

Read 2 more answers

A tank initially has 300 gallons of a solution that contains 50 lb. of dissolved salt. A brine solution with a concentration of

belka [17]

Let s(t) be the amount of salt in the tank at time t. Then s(0) = 50 lb.

Salt flows into the tank at a rate of

(2 gal/min) (6 lb/gal) = 12 lb/min

and flows out at a rate of

(2 gal/min) (s(t)/300 lb/gal) = s(t)/150 lb/min

so that the net rate at which salt is exchanged through the tank is

ds(t)/dt = 12 - s(t)/150 … (lb/min)

Solve for s(t). The DE is separable, so we have

ds/dt = 12 - s/150

150 ds/dt = 1800 - s

150/(1800 - s) ds = dt

Integrate both sides to get

-150 ln|1800 - s| = t + C

Solve for s :

ln|1800 - s| = -t/150 + C

1800 - s = exp(-t/150 + C )

1800 - s = C exp(-t/150)

s = 1800 - C exp(-t/150)

Now given that s(0) = 50, we solve for C :

50 = 1800 - C exp(-0/150)

50 = 1800 - C

C = 1750

Then the amount of salt in the tank at any time t ≥ 0 is

s(t) = 1800 - 1750 exp(-t/150)

To find the time it takes for the tank to hold 100 lb of salt, solve for t in

100 = 1800 - 1750 exp(-t/150)

1700 = 1750 exp(-t/150)

34/35 = exp(-t/150)

ln(34/35) = -t/150

t = -150 ln(34/35) ≈ 4.348

So it would take approximately 4.348 minutes.

By the way, we didn't have to solve for s(t), we could have instead stopped with

-150 ln|1800 - s| = t + C

Solve for C - this C is not the same as the one we found using the other method. s(0) = 50, so

-150 ln|1800 - 50| = 0 + C

C = -150 ln|1750|

==> t = 150 ln(1750) - 150 ln|1800 - s|

Then s(t) = 100 lb when

t = 150 ln(1750) - 150 ln(1700)

t = 150 ln(1750/1700)

t = 150 ln(35/34)

t ≈ 4.348

5 0

3 years ago