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mr_godi [17]
4 years ago
7

Can you please help please

Mathematics
1 answer:
Aneli [31]4 years ago
8 0
2 1/2 hours = 5/2 hours
He spent 1/5 of that time
5/2 x 1/5 = 1/2
1/2 of an hour is 30 minutes
You spent 30 minutes writing your blog
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What is the simplified from of the expression? r^-7 + s^-12
pochemuha

Answer:

2

Step-by-step explanation:

3 0
3 years ago
Geologists estimate the time since the most recent cooling of a mineral by counting the number of uranium fission tracks on the
Oliga [24]

Answer:

(a) The value of P (X = 7) is 0.1388.

(b) The value of P (X ≥ 3) is 0.9380.

(c) The value of P (2 < X < 7) is 0.5433.

(d) \mu_{X}=6

(e) \sigma_{X}=2.45

Step-by-step explanation:

Let <em>X</em> = number of uranium fission tracks on per cm² surface area of the mineral.

The average number of track per cm² surface area is, <em>λ</em> = 6.

The random variable <em>X</em> follows a Poisson distribution with parameter <em>λ</em> = 6.

The probability mass function of a Poisson distribution is:

P(X=x)=\frac{e^{-\lambda}\lambda^{x}}{x!};\ x=0, 1, 2, 3...

(a)

Compute the value of P (X = 7) as follows:

P(X=6)=\frac{e^{-6}(6)^{7}}{7!}=\frac{0.0025\times 279936}{5040}=0.1388

Thus, the value of P (X = 7) is 0.1388.

(b)

Compute the value of P (X ≥ 3) as follows:

P (X ≥ 3) = 1 - P (X < 3)

              = 1 - P (X = 0) - P (X = 1) - P (X = 2)

              =1-\frac{e^{-6}(6)^{0}}{0!}-\frac{e^{-6}(6)^{1}}{1!}-\frac{e^{-6}(6)^{2}}{2!}\\=1-0.00248-0.01487-0.04462\\=0.93803\\\approx0.9380

Thus, the value of P (X ≥ 3) is 0.9380.

(c)

Compute the value of P (2 < X < 7) as follows:

P (2 < X < 7) = P (X = 3) + P (X = 4) + P (X = 5) + P (X = 6)

                   =\frac{e^{-6}(6)^{3}}{3!}+\frac{e^{-6}(6)^{4}}{4!}+\frac{e^{-6}(6)^{5}}{5!}+\frac{e^{-6}(6)^{6}}{6!}\\=0.08924+0.13385+0.16062+0.16062\\=0.54433\\\approx0.5443

Thus, the value of P (2 < X < 7) is 0.5433.

(d)

The mean of the Poisson distribution is:

\mu_{X}=\lambda=6

(e)

The standard deviation of the Poisson distribution is:

\sigma_{X}=\sqrt{\sigma^{2}_{X}}=\sqrt{\lambda}=\sqrt{6}=2.4495\approx2.45

5 0
4 years ago
Calculate the volume of a cone with r=6.2 and h=10.9 and Pi=3.14
slega [8]

Answer: The volume(v) is 438.77.

Explanation: The formula for a right circular cone is in the image.

5 0
3 years ago
Help me please please please
kirza4 [7]

Answer:

3 and 5 are the correct answer's

Step-by-step explanation:  

12 6 3 all make up the facts that each hat can hold about 56.5 cubic inches of candy, and a hat with a radius of 4 inches and a height of 5 inches would hold more candy than the hats Cary's mom is using.

7 0
3 years ago
Could someone please help!!
Nastasia [14]
<span>The first two terms of a geometric sequence are a1=1/3 and a2=1/6. what is a8 the 8th term?
r=(1/6)/(1/3) = 1/2
a(8)= ar^7 = (1/3)(1/2)^7 = 1/3*1/128= 1/384</span>
6 0
3 years ago
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