Simplify using the order of operations.<br> 3/8-1/9

For what value of y does 125=(1/25)^(y-1)?

Romashka [77]

Answer:

y = -1/2 is the answer to 125=(1/25)^(y-1)

7 0

3 years ago

the current temperature in smalltown is 20 degrees fahrenheit. this is 6 degrees less than twice the temperature that it was six

Fed [463]

The answer should be 4.

Divide 20 by 2. Thus then you subtract 6.

Your final answer is 4.
$20 \div 2 - 6$

7 0

3 years ago

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

Need to be done asap!!! I will give u brainliest if ur right

alisha [4.7K]

The answer is the first one, A

3 0

4 years ago

What is 5,254,071,926 written in standard form

Elis [28]

5.254071926×10^9
Standard form is taking a large number and putting it in a form where the number is smaller than 10. To do that (using the number above) you would take the first number which is 5 and then make every number after it part of a decimal. You then use [×10^x] (multiplied by 10 to the power of the amount of numbers after the decimal point (In this case 9)) to show others that to find the full number you multiply the decimal by 10 to the power of 9.

5 0

4 years ago

Simplify using the order of operations. 3/8-1/9