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2 years ago

PLEASE HELP 100 POINTS

Mathematics

2 answers:

Karolina [17]2 years ago

8 0

Step-by-step explanation:

the total surface area is the sum of the individual areas.

we have the ground area : a 6×6 square. = 36 cm²

and we have 4 equal triangles.

the area of a triangle is baseline × height / 2.

which is for each of these triangles

6 × 12 / 2 = 3 × 12 = 36 cm²

so, the total surface area of the pyramid is

36 + 4×36 = 5×36 = 180 cm²

attashe74 [19]2 years ago

5 0

Solution:

We know that:

Surface area of square pyramid = Sum of the area of the faces.

This means that:

Surface area of square pyramid = Area of square + 4(Area of triangle)

First, let's find the area of the triangle and square. Then, substitute them in the surface area equation to find the surface area of the pyramid.

Finding the area of a triangle:

1/2 x 12 x 6
=> 6 x 6
=> 36 cm²

Finding the area of a square:

6 x 6
=> 36 cm²

Finding the surface area of the pyramid:

Surface area of square pyramid = Area of square + 4(Area of triangle)
Surface area of square pyramid = 36 + 4(36)
=> 36 + 144
=> 180 cm²

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What is the median pumpkin weight?

jarptica [38.1K]

Answer:

Step-by-step explanation:

The median of a data set is found by putting the data set in ascending numerical order and identifying the middle number. If there are an odd number of data values in the data set, the median is a single number. If there are an even number of data values in the data set, the median is the average of the two middle numbers. Sorting the data set for the values entered above we have:

$10, 12, 14, 16, 18, 20, 22, 24$

Since there is an even number of data values in this data set, there are two middle numbers. With 8 data values, the middle numbers are the data values at positions 4 and 5. These are 16 and 18. The median is the average of these numbers. We have

${\frac{ 16 + 18 }{2}}$

Therefore, the median is

$17$

6 0

2 years ago

PLEASE HELP! Probability!

wlad13 [49]

2+3=5 no
2+5=7 no
2+8=10 yes (if zero counts as an even number)
5+3=8 yes
5+8=13 no
8+3=11
So 2/6 = 1/3 1/3 should be the answer

6 0

3 years ago

Read 2 more answers

A particular concentration of a chemical found in polluted water has been found to be lethal to 40% of the crayfish that are exp

Jet001 [13]

Answer:

a) $P(X=13)=(24C13)(0.4)^{13} (1-0.4)^{24-13}=0.0608$

$P(X=17)=(24C17)(0.4)^{17} (1-0.4)^{24-17}=0.0017$

$P(X=13 U X=17) = 0.0608+0.0017=0.0624$

b) $P(X \geq 17)=0.000427$

c) $P(X \geq 16)= 1-0.000427=0.9996$

d) $E(X)= np = 22*0.4=8.8$

e) $Var(X) = np(1-p)= 22*0.4*(1-0,4)=5.28$

Step-by-step explanation:

1) Previous concepts

The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".

2) Solution to the problem

Let X the random variable of interest, on this case we now that:

$X \sim Binom(n=24, p=0.4)$

The probability mass function for the Binomial distribution is given as:

$P(X)=(nCx)(p)^x (1-p)^{n-x}$

Where (nCx) means combinatory and it's given by this formula:

$nCx=\frac{n!}{(n-x)! x!}$

3) Part a

$P(X=13)=(22C13)(0.4)^{13} (1-0.4)^{22-13}=0.0336$

$P(X=17)=(22C17)(0.4)^{17} (1-0.4)^{22-17}=0.00035$

$P(X=13 U X=17) = 0.0336+0.00035=0.0340$

4) Part b

$P(X \geq 17)=P(X=17)+P(X=18)+P(X=19)+P(X=20)+P(X=21)+P(X=22)$

$P(X=17)=(22C17)(0.4)^{17} (1-0.4)^{22-17}=0.00035$

$P(X=18)=(22C18)(0.4)^{18} (1-0.4)^{22-18}=0.0000651$

$P(X=19)=(22C19)(0.4)^{19} (1-0.4)^{22-19}=0.00000914$

$P(X=20)=(22C20)(0.4)^{20} (1-0.4)^{22-20}=0.000000914$

$P(X=21)=(22C21)(0.4)^{21} (1-0.4)^{22-21}=5.81x10^{-8}$

$P(X=22)=(22C22)(0.4)^{22} (1-0.4)^{22-22}=1.76x10^{-9}$

$P(X \geq 17)=0.000427$

5) Part c

$P(X \leq 16)=1-P(X>16)=1-P(X\geq 17) = 1-[P(X=17)+P(X=18)+P(X=19)+P(X=20)+P(X=21)+P(X=22)]$

$P(X \geq 16)= 1-0.000427=0.9996$

6) Part d

The expected value is:

$E(X)= np = 22*0.4=8.8$

7) Part e

The variance is given by:

$Var(X) = np(1-p)= 22*0.4*(1-0,4)=5.28$

3 0

3 years ago

A new computer can complete a complex biochemistry calculation in 7 hours less than an older-model computer. Working together, t

Alchen [17]

The rate a computer works is 1/time. Working together, you add the rates.
Let new computer be x, old computer be y.
x = y - 7

$\frac{1}{x} + \frac{1}{y} = \frac{1}{13} \\ \\ \frac{1}{y-7}+\frac{1}{y} = \frac{1}{13} \\ \\ \frac{2y-7}{y(y-7)} = \frac{1}{13} \\ \\ y(y-7) = 13(2y-7) \\ \\ y^2-33y+91 = 0 \\ \\ y = 29.96 \\ \\ x = y-7 = 29.96-7 = 22.96$
Rounded to nearest tenth gives:
x = 23 hours

6 0

3 years ago

PLZ HELP ME!!!!!! ASAP!! PLZ EXPLAIN YOUR ANSWERS THOROUGHLY!! giving 20 points

vredina [299]

The answer would be C because the inequality is greater than 70 but less then 80.

4 0

3 years ago