Answer:
x = 960.4
Step-by-step explanation:
980 = 1000[tex]e^{kt}[/tex]
.98 = [tex]e^{10 k}[/tex]
ln(.98) = 10k ln(e)
k = ln(.98)/10
k=-0.00202
~~~~~~~~~~~~~~
x = 1000[tex]e^{20 *-.00202}[/tex]
x = 960.4
The amount of the material right after 20 years will be x = 960.4.
What is an exponential expression?Powers can simply be expressed in concise form using exponential expressions. The exponent shows how many times the base has been multiplied. Since 2 is the "base" and 5 is the "exponent," it can be represented as 2x2x2x2=25 for the number 32. This phrase should be understood as "two to the fifth power."
Given that radioactive material is known to decay at a yearly rate proportional to the amount at each moment. There were 1000 grams of the material 10 years ago. There are 980 grams right now.
The amount of the material will be calculated as,
980 = 1000
[tex]0.98 = e^{10k}[/tex]
ln(.98) = 10k ln(e)
k = ln(.98)/10
k=-0.00202
The value after 20 years will be,
[tex]x = 1000e^{20\times 0.00202}[/tex]
x = 960.4
Therefore, the amount of the material right after 20 years will be x = 960.4.
To know more about an exponential expression follow
https://brainly.com/question/2456547
#SPJ5
The original price of a set lunch was 30 dollars. It is now sold at a 20%
discount. There is an extra discount of 10% for students. How much
should a student pay to order a set lunch?
Solve the formula for t
Answer:
Step-by-step explanation:
S - 4πc^2 = 6πct
t = (S - 4πc^2)/6πc
t = S/(6πc) - 2/3 c
assuming c ≠ 0
Applying for a loan. What separates me from other applicants applying for this money?
Answer:
Step-by-step explanation:
You could have a good credit score and good credit history.
According to the WHO report, girls who are one month old have a mean head circumference of 36.6 centimeters with a standard deviation of 1.2 centimeters. As with most body measurements, head circumference has a normal probability distribution. Medscape defines microcephaly (small head syndrome) as a head circumference that is more than two standard deviations below the mean. What is the probability that a one-month old girl will be categorized as having microcephaly
Answer:
0.0228 = 2.28% probability that a one-month old girl will be categorized as having microcephaly
Step-by-step explanation:
Normal Probability Distribution
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Medscape defines microcephaly (small head syndrome) as a head circumference that is more than two standard deviations below the mean. What is the probability that a one-month old girl will be categorized as having microcephaly?
Probability of a z-score of -2 or less, which is the p-value of Z = -2.
Looking at the z-table, Z = -2 has a p-value of 0.0228.
0.0228 = 2.28% probability that a one-month old girl will be categorized as having microcephaly
HELPP
-1-3(5m+8) ≥-85
i need help :D
Answer:
- 1 - 3(5m + 8) ≥ -85
-1 - 15m - 24 ≥ -85
-15m ≥ -85 + 1 + 24
-15m ≥ 25 - 85
-15m ≥ -60
(-1)(-15)m ≤ -60(-1)
15m ≤ 60
m ≤ 4
solve the system of equations using substitution or graphing.
Step-by-step explanation:
I think substitution would be the easiest since you already have one of the variables solved for.
[tex]y=-x^2+4x+5\\y=x+1\\x+1=-x^2+4x+5\\x^2-3x-4=0\\(x-4)(x+1)=0\\x-4=0\\x=4\\x+1=0\\x=-1[/tex]
(You can just set the equations equal to each other since they both equal y).
Now, to get the points, plug in x = 4 and x = -1 into one of the equations (I'm going to plug them into y = x+1 because that one is much simpler)
[tex]y(4)=4+1\\y(4)=5\\y(-1)=-1+1\\y(-1)=0[/tex]
So, your final points are:
(4,5) and (-1,0)
Answer: A
Step-by-step explanation:
We can use substitution to solve this problem. Since we are given y=-x²+4x+5 and y=x+1, we can set them equal to each other.
-x²+4x+5=x+1 [subtract both sides by x]
-x²+3x+5=1 [subtract both sides by 1]
-x²+3x+4=0
Now that we have the equation above, we can factor it to find the roots.
-x²+3x+4=0 [factor out -1]
-1(x²-3x-4)=0 [factor x²-3x-4]
-1(x+1)(x-4)=0
This tells us that x=-1 and x=4.
We can narrow down our answer to A, but let's plug in those values to be sure it is correct.
-(-1)²+4(-1)+5=(-1)+1 [exponent]
-1+4(-1)+5=-1+1 [multiply]
-1-4+5=-1+1 [add and subtract from left to right]
0=0
-------------------------------------------------------------------------------------------
-(4)²+4(4)+5=(4)+1 [exponent]
-16+4(4)+5=4+1 [multiply]
-16+16+5=4+1 [add and subtract from left to right]
5=5
Therefore, we can conclude that A is the correct answer.
HELP ME PLSSSSSSSS I tryed to solvessss
Answer:
x≥-4
Step-by-step explanation:
marking brainliest for a simple math problem
Answer:
B. 88
Step-by-step explanation:
the total data = 1+2+4+5 = 12
the median is (a6+a7) /2
a6 = 87, a7 = 89
so, the median = (87+89)/2 = 88
Answer:
B. 88
--
the median is (a6+a7) /2
a6 = 87, a7 = 89
so, the median =[tex]\frac{87+89}{2}[/tex]= 88
Police Chase: A speeder traveling 40 miles per hour (in a 25 mph zone) passes a stopped police car which immediately takes off after the speeder. If the police car speeds up steadily to 55 miles/hour in 10 seconds and then travels at a steady 55 miles/hour, how long and how far before the police car catches the speeder who continued traveling at 40 miles/hour
Answer:
a. 18.34 s b. 327.92 m
Step-by-step explanation:
a. How long before the police car catches the speeder who continued traveling at 40 miles/hour
The acceleration of the car a in 10 s from 0 to 55 mi/h is a = (v - u)/t where u = initial velocity = 0 m/s, v = final velocity = 55 mi/h = 55 × 1609 m/3600 s = 24.58 m/s and t = time = 10 s.
So, a = (v - u)/t = (24.58 m/s - 0 m/s)/10 s = 24.58 m/s ÷ 10 s = 2.458 m/s².
The distance moved by the police car in 10 s is gotten from
s = ut + 1/2at² where u = initial velocity of police car = 0 m/s, a = acceleration = 2.458 m/s² and t = time = 10 s.
s = 0 m/s × 10 s + 1/2 × 2.458 m/s² (10)²
s = 0 m + 1/2 × 2.458 m/s² × 100 s²
s = 122.9 m
The distance moved when the police car is driving at 55 mi/h is s' = 24.58 t where t = driving time after attaining 55 mi/h
The total distance moved by the police car is thus S = s + s' = 122.9 + 24.58t
The total distance moved by the speeder is S' = 40t' mi = (40 × 1609 m/3600 s)t' = 17.88t' m where t' = time taken for police to catch up with speeder.
Since both distances are the same,
S' = S
17.88t' = 122.9 + 24.58t
Also, the time taken for the police car to catch up with the speeder, t' = time taken for car to accelerate to 55 mi/h + rest of time taken for police car to catch up with speed, t
t' = 10 + t
So, substituting t' into the equation, we have
17.88t' = 122.9 + 24.58t
17.88(10 + t) = 122.9 + 24.58t
178.8 + 17.88t = 122.9 + 24.58t
17.88t - 24.58t = 122.9 - 178.8
-6.7t = -55.9
t = -55.9/-6.7
t = 8.34 s
So, t' = 10 + t
t' = 10 + 8.34
t' = 18.34 s
So, it will take 18.34 s before the police car catches the speeder who continued traveling at 40 miles/hour
b. how far before the police car catches the speeder who continued traveling at 40 miles/hour
Since the distance moved by the police car also equals the distance moved by the speeder, how far the police car will move before he catches the speeder is given by S' = 17.88t' = 17.88 × 18.34 s = 327.92 m
I need help please and thank you.
Answer:
option a.
[tex] + - \frac{13}{5} [/tex]
Step-by-step explanation:
[tex]25x^2\: - \:169 = 0 [/tex]
[tex]25x^2 = 169[/tex]
[tex] {x}^{2} = \frac{169}{25} [/tex]
[tex]x = + - \sqrt{ \frac{169}{25} } [/tex]
[tex]x = + - \frac{13}{5} [/tex]
Cell Phone Service
Cellular phone service is available for $31 per month for 666 minutes. What is the
monthly cost per minute? Round your answer to the nearest tenth of a cent.
The cost for the phone service is
cents per minute.
9514 1404 393
Answer:
4.7¢/min
Step-by-step explanation:
To find the cost in cents per minute, divide the cost in cents by the number of minutes.
$31.00/(666 min) = (3100¢)/(666 min) ≈ 4.7¢/min
A student has test scores of 75 and 82respectively. What is the student’s average score for a third test
Answer:
78.5 (I think 90% sure)
Step-by-step explanation:
sum of both scores
75+82 = 157
average for a third test
157÷2=78.5
OMG THIS IS SO HARD
Answer:
Answer to the first question is D. Answer to the second question is also D.
Step-by-step explanation:
First question:
All the sides of the square are equal meaning you just have to multiply 1 side by 4 to get the perimeter(all the sides added together.) If one side is (s+3) then you either add that to itself 4 times or multiply it by 4. It's the same thing so it's 4(s+3) and (s+3)+(s+3)+(s+3)+(s+3).
Second question:
Adding a negative number is equivalent to subtracting a positive number. In this case, 59.2-84.7 = 59.2+(-84.7)
HELP
Identify the domain of the function shown in the graph.
Answer:
D = [4, 10]
Step-by-step explanation:
Since the line starts when x = 4, the domain begins there. And since the line ends when x=10, the domain ends there.
Problem is in the picture below
Answer:
90 maybe is a correct answer
Answer:
Y=40°
Step-by-step explanation:
VUW~YXZ
VWU~YZX
YXZ+XYZ+YZX=180°
70°+XYX+70°=180°
140°+XYZ=180°
XYZ=180°-140°
XYZ=40°
Jen recently rode her bicycle to visit her friend who lives 6 miles away. On her way there, her average speed was 8 miles per hour faster than on her way home. If jen
spent a total of 2 hours bicycling find the two rates.
the answer is in the picture above
Xavier is testing different types of planting soil to determine which type is most effective in growing blueberry bushes. He purchases two different brands of planting soil from a local store. Xavier applies Brand A to an area of the yard that receives full sunlight and Brand B to another area of the yard that is in partial sunlight. He waters the area with Brand B daily; he waters the area with Brand A every other day. At the end of the study, Xavier concludes Brand A is more effective in growing blueberry bushes. Why is his conclusion not valid?
Answer:
He did not control for lurking variables and their impacts on the results of his experiment. Amount of sunlight and water received are two outside variables(or confounding variables) that may impact the growth of his plants and influence the results. He needs to apply the same amount of sunlight and water to each plant within a different planting soil in order to rule out the influence of those two variables and test the sole effect of the soil brand on the plant growth. Otherwise, it would be hard to determine whether his plant growth was because of the soil brand or the different amounts of sunlight and water received
Answer:
Invalid
Step-by-step explanation:
Xavier did not control variables or the impacts of the results. Confounding variable being sunlight and water received are two outside variables that can impact growth influence results. Within a different planting soil, Xavier will apply the same amount of sunlight & water to each plant to rule out the influence of those two variables. The test for sole effect on the plant with growth otherwise be determine. Is the plant growth because of the soil brand or the different amounts of sunlight and water received? This could and will impaired the results of this experiment, therefore, making it invalid.
simplify 3xy + x 2 - 4xy + 2xupper2y
O EXPONENTAL AND LOGARITHMIC FUNCTIONS
Finding the initial or final amount in a word problem on...
An initial amount of money is placed in an account at an interest rate of 2% per year, compounded continuously. After two years, there is $1269.79 in the
account. Find the initial amount placed in the account. Round your answer to the nearest cent.
Answer:
$ 1220.00
Step-by-step explanation:
1269.79 = A [tex]e^{.02 * 2}[/tex]
1269.79 /A = [tex]e^{.04}[/tex]
ln(1269.79 /A) = .04 ln(e)
ln(1269.79 /A) = .04
1269.79 /A = [tex]e^{.04}[/tex]
1269.79 /A = 1.0408
A = 1269.79 / 1.0408
$ 1220.00
Use the appropriate reciprocal identity to find the exact value of sin for the given value of csc . Rationalize denominators when applicable. csc 27/5 sin
Answer:
[tex]\sin(\theta) = \frac{5}{27}[/tex]
Step-by-step explanation:
Given
[tex]\csc(\theta) = \frac{27}{5}[/tex]
Required
Determine [tex]\sin(\theta)[/tex]
In trigonometry identity;
[tex]\sin(\theta) = \frac{1}{\csc(\theta)}[/tex]
So, we have:
[tex]\sin(\theta) = \frac{1}{\frac{27}{5}}[/tex]
Take inverse of the fraction
[tex]\sin(\theta) = \frac{5}{27}[/tex]
Help please!!!!!!!!!!!!!!!!!!
Express the following composite numbers as products of prime factors 64
Answer:
64 is a composite number, and it is 8 squared. 64 = 1 x 64, 2 x 32, 4 x 16, or 8 x 8. Factors of 64: 1, 2, 4, 8, 16, 32, 64. Prime factorization: 64 = 2 x 2 x 2 x 2 x 2 x 2, which can also be written 64 = 2⁶.
The average THC content of marijuana sold on the street is 9.6%. Suppose the THC content is normally distributed with standard deviation of 1%. Let X be the THC content for a randomly selected bag of marijuana that is sold on the street. Round all answers to 4 decimal places where possible,
a. What is the distribution of X? X ~ N(
9.6
Correct,
1
Correct)
b. Find the probability that a randomly selected bag of marijuana sold on the street will have a THC content greater than 9.8.
c. Find the 67th percentile for this distribution.
%
Answer:
Im sorry but why is this a question? Like what school gives this out
A bricklayer needs to order 6 300 kg of building sand.
a) Write 6 300 kg in grams, giving your answer in standard form.
One grain of this sand approximately weighs 7 x 10°g.
b) How many grains of sand are there in 6 300 kg of sand? Give your answer in standard from.
Answer:
It would be 6300000. I can't write this in standard form.
Step-by-step explanation:
Answer:
6.3 x 10^6
Step-by-step explanation:
Answer correctly and 40 points. Thx. Will report if wrong. ASAP plz! Thx!
Answer:
-7
Step-by-step explanation:
if you multiply by 7 positive it wont work because u cant cancel 7x out and a fraction wont work because theres no fraction involved in this so ur answer is A
If f(x) = 4x and gx) = 2x- 1, what is g(f(-2))?
-17
-13
-8
-5
Answer:
-17
Step-by-step explanation:
We are given these following functions:
[tex]f(x) = 4x[/tex]
[tex]g(x) = 2x - 1[/tex]
g(f(-2))
First we find f when x = -2, then we find g for this value(f when x = -2). So
[tex]f(-2) = 4(-2) = -8[/tex]
[tex]g(f(-2)) = g(-8) = 2(-8) - 1 = -16 - 1 = -17[/tex]
Thus -17 is the answer.
Point Q is the centroid of △ABC. QF = _____ centroid
Answer:
Q is the centroid the after you can do it your self by looking forward
Answer:
QF = 5
Step-by-step explanation:
On a median the distance from the vertex to the centroid is twice as long as the distance from the centroid to the midpoint, that is
QF = [tex]\frac{1}{2}[/tex] BQ = [tex]\frac{1}{2}[/tex] × 10 = 5
NEED HELP ASAP GIVING BRAINLIEST!!!!!!!!!!!!!!!!!!
Answer:
option D
Step-by-step explanation:
[tex]sin^2 ( \frac{3\pi}{2}) + cos^2(\frac{3\pi}{2}) = 1\\\\( -1)^2 + 0^2 = 1[/tex]
Explanation:
[tex]sin x = cos( \frac{\pi}{2} - x)\\\\sin(\frac{3\pi}{2}) = cos ( \frac{\pi}{2} - \frac{3\pi}{2})\\[/tex]
[tex]=cos(\frac{\pi - 3\pi}{2})\\\\ =cos(\frac{2\pi}{2})\\\\=cos \ \pi\\\\= - 1[/tex]
Therefore ,
[tex]sin^2( \frac{3\pi}{2}) = ( - 1)^2[/tex]
Solve. SHOW ALL YOUR WORK
2.51 * .2
77/ 1.2
Answer:
0.502
64.1666
Step-by-step explanation:
Detained explanation of the product operation and division operation is attached below.
2.51 * 0.2 = 0.502
(after multiplying) the number of decimal places of the town values is added and counted from the right in the product to place the data Comal point appropriately.
77/1.2 ; values were multiplied by 10 in other to obtain inter values for the denominator.
what is the sum of a 7 term geometric series if the first term is 6 the last term is -24576 and the common ratio is -4
Answer:
Sum = 19,662
Step-by-step explanation:
Given that this is a finite geometric series (meaning it stops at a specific term or in this case -24,576), we can use this formula:
[tex]\frac{a(1-r^n)}{1-r}[/tex], where a is the first term, r is the common ratio, and n is the number of terms.
Substituting for everything and simplifying gives us:
[tex]\frac{6(1-(-4)^7)}{1-(-4)} \\\\\frac{6(16385}{5}\\ \\\frac{98310}{5}\\ \\19662[/tex]