What is the surface area of the square pyramid?

Explain the differences between adding and multiplying radical expressions using 2 examples you create.

ivann1987 [24]

Answer:

When you multiply radical expressions you multiply the numbers under the radical symbols.3–√×7–√=21−−√

When you add radical expression you CANNOT add the numbers under the radical symbols.

3–√+7–√≠10−−√

Step-by-step explanation:

6 0

2 years ago

A rectangular field is 95 meters long and 65 meters wide. Give the length and width of another rectangular field that has the sa

Lena [83]

Answer:

There are a ton of answers. For instance, 1m by 159m.

Step-by-step explanation:

The formula for the area is $a=l*w$ , where $l$ and $w$ are constants.

The formula for perimeter is $p=2l+2w$

The question wants another rectangle that has the same perimeter, but a smaller area.

The perimeter of the two fields has to be:

$p=(2*95)+(2*65)\\p=190+130\\p=320$

Thankfully, the question never specified how much smaller the area has to be. So let's go to the logical extreme and make it 1 meter wide. To conserve the perimeter, we'd have to add the removed 64 meters to the original 95 meters of length, resulting in a rectangle with a width of 1m and a length of 159m. This results in an area of exactly 159 $m^{2}$ . The original rectangle had an area of 6175 $m^{2}$ . Mission accomplished!

But why stop there? Let's go even further down this rabbit hole!

Instead of 1, why don't we take it several steps further and use 0.0000001? At that point, the length would end up being 159.9999999m.

The area would be 0.00001599999999 $m^{2}$ .

Let's go further!!

Width: 0.00000000000000000001

Length: 159.99999999999999999999

Area: 0.00000000000000000001599999999999999999999 (approximate).

One more, for old time's sake.

Width: 0.00000000000000000000000000000000000000000000000001m

Length: 159.99999999999999999999999999999999999999999999999999m

Area: 0.00000000000000000000000000000000000000000000000015999999999999999999999999999999999999999999999999999 $m^{2}$

At that point, there's so little area in the plot of land that you could claim it has no area!

5 0

2 years ago

What property shows that 2/5 x 1 = 40/100

nekit [7.7K]

I believe the commutative property on multiplication

i hope this helped

5 0

2 years ago

If A represents the number of apples purchased at .15 cents each, and B represents the number of banana's purchased at.10 each ,

grigory [225]

Are there options or do u have to type it??

7 0

3 years ago

At a certain coffee shop, all the customers buy a cup of coffee; some also buy a doughnut. The shop owner believes that the numb

Zinaida [17]

Answer:

a) 0.2514

b) No

c) 0.2611

Step-by-step explanation:

For coffee cups sold daily

Mean(μ) = 320 cups

Standard deviation (σ) = 20 cups

For doughnut sold daily

Mean(μ) = 150 doughnut

Standard deviation (σ) = 12 doughnut

Let X be the random variable representing the number of cups.

Let y be the random variable representing the number of doughnuts.

a) The shop is opened everyday except Sunday's. This means that the shop is opened 6 times in a week.

The probability that he will sell more 2000 cups of coffee in a week = Pr(x>2000)

Using normal distribution

Z = (x - μ)/σ

Z = (2000 - 6(320))/6(20)

Z = (2000 - 1920) / 120

Z = 80/120

Z = 0.67

From the normal distribution table, 0.67 = 0.2486

Φ(z) = 0.2486

Recall that if Z is positive,

Pr(x>a) = 0.5 - Φ(z)

Pr(x>2000) = 0.5 - 0.2486

= 0.2514

b) On each cup of coffee, he makes a profit of 50 cents and makes a profit of 40 cents on each doughnut. We have 0.5x + 0.4y

Z = (x - μ) / σ

Z = (300 - (0.5*320 + 0.4*150)) / √0.5^2*20^2 + 0.4^2*12^2

Z = (300 - (160+60)) / √100+23.04

Z = (300 -220)/√123.04

Z = 80/11.09

= 7.02

Since 300 is more than 7 standard deviation from the mean and the value of z cannot be found in the normal distribution table, then he has NO reasonable chance to earn a profit more than 300.

c) The probability that on any given day he will sell a doughnut to more than half of his coffee customers = Pr(y - 0.5x > 0)

From normal distribution,

Z = (x - μ) / σ

Z = (0 - (150 - 0.5*320)) / √12^2 + 0.5^2*20^2

Z = (0 - (150 - 160)) / √144 + 100

Z = (0 -(-10))/√244

Z = 10/15.62

= 0.64

From the normal distribution table, 0.64 = 0.2389

Φ(z) = 0.2389

Recall that if Z is positive,

Pr(x>a) = 0.5 - Φ(z)

Pr(y - 0.5x >0) = 0.5 - 0.2389

= 0.2611

6 0

2 years ago