After x half-lifes, the amount of the isotope is:
A(x*T) = 90mg*e{-x*ln(2)}
And after 70 days, there are 5.628 mg
What is the half-life?
We define the half-life as the time such that the inital amount of a given substance reduces to half of it.
If the half-life is T, the amount of the substance can be written as:
A(t) = a*e^{-λ*t}
Where λ = ln(2)/T.
and a is the initial amount.
In this case, T = 17.5 days, then:
λ = ln(2)/17.5 days = 0.0396 / day
And we also have a = 90mg
Then the exponential equation is:
A(t) = 90mg*e^{-t*0.0396 / day}
After x half-lifes, the amount of the isotope left is:
A(x*T) = 90mg*e^{-x*T*ln(2)/T} = 90mg*e^{-x*ln(2)}
And after 70 days the amount is:
A(70 days) = 90mg*e^{-70 days*0.0396 / day} = 5.628 mg
If you want to learn more about exponential decays, you can read:
https://brainly.com/question/11464095
Answer:
Y=90mg(0.5)^5
1.86 after 70 days
Step-by-step explanation:
What is the most common amount of hours students spent studying? (2 points)
A line plot with the title, time students spent studying, and the line is measured in hours. The horizontal line goes from one third to three. In between, there are seven tick marks labeled as two thirds, one, one and one third, one and two thirds, two, two and one third, two and two thirds. The tick mark one third has two xs, the tick mark two thirds has one x, the tick mark one has four xs, the tick mark one and one third has three xs, the tick mark one and two thirds has three xs, the tick mark two has five xs, the tick mark two and one third has three xs, the tick mark two and two thirds has two xs, and the tick mark three has two xs.
a
1 hour
b
one and one third hours
c
2 hours
d
3 hours
What is the rule and how do you find n? 100 points and brainliest to answer!
Answer:
n = 6
Step-by-step explanation:
Let's convert the x and y values into (x,y) form.
(x, y) ⇒ (3, 5), (4, 7), (n, 11), (8, 15)
Now, let's find the rule in slope intercept form. To find the equation in slope intercept form, pick any two points. Then find the slope of the line.
⇒ (3, 5) and (4, 7)
Now, find the slope using the slope formula.
[tex]\dfrac{y_{2} - y_1}{x_2 - x_1} = \text{Slope}[/tex]
[tex]\rightarrow \dfrac{7 - 5}{4 - 3} = \text{Slope}[/tex]
[tex]\rightarrow \dfrac{2}{1} = 2 =\text{Slope}[/tex]
Now, let's use point slope form to find the equation in slope intercept form.
[tex]y - 5 = 2(x - 3)[/tex]
[tex]\rightarrow y - 5 = 2x - 6[/tex]
[tex]\rightarrow y = 2x - 1 \ \ \ \ \ (\text{Rule})[/tex]
Now, substitute the value of y into the equation.
[tex]11 = 2x - 1[/tex]
[tex]\rightarrow 12 = 2x[/tex]
[tex]\rightarrow \boxed{x = n = 6}[/tex]
Take two points find equation
(3,5)(4,7)Slope:-
m=7-5/4-3=2Equation in point slope form
y-5=2(x-3)y=2x-6+5y=2x-1Now put n
11=2n-12n=12n=6The circumference of a circle is 43.96 yards. What is the circle's radius?
Answer:
Step-by-step explanation:
Radius = circumference / 2π
= 43.96 / 2π
= 7.00 yards to the nearest hundredth.
helllllppp!!!!!!!!!!!!11 marking brainliest!
Hello!
Let the unknown number be x.
Subtract 5:
x-5
Double the result: (multiply the result times 2):
2(x-5)
Hope everything is clear.
Let me know if you have any questions!
#KeepLearning
:-)
The ratio of red candy to green candy in a bag is 3 to 4
If there were 36 pieces of green candy in the bag, how many pieces of candy in the bag were red?
Answer:
27
Step-by-step explanation:
we know that 4 multiplied with something is 36
=> 4x = 36
=> x = 36/4
=> x = 9
so we have to multiply 3 with 9
=> 3*9 = 27
Which of the following inequalities matches the graph?
Answer:
x ≤ -7
Step-by-step explanation:
On the graph we can see that:
-the pink solid line is where x= -7 and y can have any value, so is either first or second choice.
-the pink area includes numbers that are equal or less then -7 ( such as -8, -9,-10,...) so the inequality must be x ≤ -7 (the second choice. )
See the line is parallel to y axis
Means x is constanty is varryingSo
x intercept is (-7,0)X is constant -7
Hence the inequality is
x≤-7You decide to put $2,000 in a savings account to save for a $3,000 down payment on a new car. If the account has an interest rate of 4% per year and is compounded monthly,
how long does it take until you have $3.000 without depositing any additional funds?
Answer:
12.5 years = 216 months
Step-by-step explanation:
4% of 2000= $80
1000/80=12.5
It will take 12.5 years to make $1000 on its own without adding additonal funds.
Find the value of x.
A. 53°
B. 72°
C. 39°
D. 48°
Answer: 53
Step-by-step explanation:
Please guys help me , i need help with this math work im not doing so good un math
Answer: If you need help on both here are both answers.... Answer 1- f(x)=6.50x+48.00 because Let
x ----> the number of adult tickets
f(x) ----> amount of money collected
To find the amount collected multiply the number of adult tickets by the cost and multiply the number of student tickets by the cost, and then sum the two quantities
The linear equation that represents this problem is
f(x)=6.50x+4.00(12)
f(x)=6.50x+48.00
and for Answer 2- Is 4
Two numbers have a sum of 1,212 and a difference of 518. What are the two numbers?
Answer:
347 and 865
Step-by-step explanation:
Let the two number be x and y
Therefore, from the given information:
x + y = 1212
x - y = 518
Rewrite both equations to make x the subject:
x = 1212 - y
x = 518 + y
Equate equations and solve for y:
1212 - y = 518 + y
694 = 2y
y = 347
Substitute found value of y into one of the equations and solve for x:
x = 518 + 347
x = 865
Therefore, the two numbers are 347 and 865
Farm workers plant 980 beans in 35 rows. How many beans do they plant in one row
The value 3pie/16 is a solution for the equation 2cos^2(4x)-1=0 true or false
Answer:
This is true
Step-by-step explanation:
Find M angle B.
Round to the nearest degree.
Answer: 41
Step-by-step explanation:
You are ordering sweatshirts for your baseball team. The bar graph shows how many of each size you will need. Which choice below is NOT true?
Answer:
- more people need extra large sweatshirts than large sweatshirts
Answer: C
Step-by-step explanation:
More people need extra large sweatshirts than large sweatshirts.
help please? with a working out would be nice
Answer:
280 cups total.
Step-by-step explanation:
Tricky. The explanation and answers are on attached images.
I am so confused. Help.
[tex]\large\sf\underline{ANSWER:}[/tex]
√3
x is the length of the third side
x²+1² = 2² { Pythagorean Theorem}
x²+1 = 4 {Simplify}
x²=3 {Subtract 1 from each side}
x=√3 {Take the square root of each side}
The Length of the third side is √3
#[tex]\large\sf\underline{CarryOnLearning}[/tex]
Find x 20 and 15 geometric mean
Answer: 17.320508075689
Step-by-step explanation:
please no guessing (WILL GIVE BRAINILIST)
STATISTICS
Answer:
#2 mean is 90.3846154 and range is 40
#3 mean 91.9230769 and range is 20
(you might have mixed the second and third graph up)
Step-by-step explanation:
The Hire Purchase priceola microwave
a deposit of $600 and equal monthly
installmentsof$4s. Howmany installmen,
Answer:
150
Step-by-step explanation:
$600/$4 =150
=150 installments
factor 1/2 out of 1/2x + 9/2
Answer:
Equation would be x + 9/2.Step-by-step explanation:
Factoring out means taking out a Number, or an unknown quantity.
So, Factor out 1/2:
New equation with old step by step:
Step 1:
Remove 1/2 from 1/2x + 9/2Step 2:
Equation should be: x + 9/2.New equation:
x + 9/2Lisa is checking out at the bookstore. Each book (b) costs $1.50 and she has a $5 off coupon she can use. She wants to spend $25 or less in the bookstore. How many books can Lisa buy?
Answer:
20
Step-by-step explanation:
Given:
Lisa is checking out at the bookstore.
Each book (b) costs $1.50 and she has a $5 off coupon she can use.
She wants to spend $25 or less in the bookstore.
Solve:
Since there is a $5 off coupon..
$1.5b - $5.00<=$25.00
$1.5b<= $30.00
$1.5b/1.5 = $30.00/1.5
b=20
Lisa can buy 20 book.
~lenvy~
Joe drove 567 miles in 9 hours.
At the same rate, how many miles would he drive in 5 hours
Answer:
answer down below
Step-by-step explanation:
it would be 315
Answer:
13 hours
Step-by-step explanation:
567/9=63
she drives 63mph
it will take her 13 hours to drive
20 = (-10) = (-20) +10
1) Is the equation up there true or false?
2) Support your decision below.
Help quick
Answer:
No, 20 ≠ -10
Step-by-step explanation:
20 = (-10) = (-20)+10
20≠-10=-20+10
20≠-10=-10
I just need 13⅗% as a decimal please thanks
the answer to 13 3/5% as a decimal
0.136
Karen has just baked 17 cookies. She wants to put them in paper bags in groups of 6. How many groups of 6can she make ? How many cookies will she have remaining ?
Answer:
She can make 2 groups of six, with five cookies remaining
Step-by-step explanation:
First, divide 17 by 6 to get 2 5/6. The whole number is the number of groups she can make, and the fraction is how many are left over. She can make two groups, with five left over.
Hopefully this helps - let me know if you have any questions!
Answer:
2 groups with 5 left over.
Step-by-step explanation:
to solve, take 17 and divide it by 2. since we only have 17 cookies, we round down no matter what. to get the left over, multiply 2 by 6, then subtract by 17.
please mark as brainlest.
André paid a $65 annual fee to register with a car rental company. The company charges $8.50 for each hour a car is rented. What is the rate of change of the function that represents André's cost for renting a car over the course of a year?
A. $8.50 per hour
B. $65 per year
C. $73.50 per hour
D. $73.50 per year
Answer:
I dont know if this is the right answer, but my best guess is that it is A.
Step-by-step explanation:
The rate of change of the function that represents André's cost for renting a car over the course of a year $8.50 per hour.
What is the rate of change?
The rate of change is the cost by which the cost of renting the car increases by. The cost of renting the car increases by $8.50 per hour.
The annual fee can be described as the fixed cost of renting the car per year.
To learn more about fixed cost, please check: https://brainly.com/question/25879561
Answer the questions in the image.
#1
Radius=9/2=4.5inArea:-
πr²4.5^2π20.25πin^263.58in^2#2
Side=a=4inArea:-
a²4²16in^2#3
Area of the white part=Area of circle-Area of square
63.585-1647.585in^2#4
Probability
16/63.5850.252#5
Probability
47.58/63.5850.75Answer:
1. 63.62 in².
2. 16 in².
3. 47.62 in².
4. 0.25 .
5. 0.74 .
Step-by-step explanation:
1.
Solution,
Given,
Diameter = 9 inch.
Now,
Area = πr²
Diameter = r²
Then,
Area = 1/4 πd²
= 1/4 π9²
= 63.62 in².
2.
Solution,
Given,
Length of a Side = 4 inch.
Now,
Area = L²
= 4²
= 16 in².
3.
Solution,
Given,
Area of the Circle = 63.62 in².
Area of the Square = 16 in².
Now,
Area of The White Part of the Circle = Area of Circle - Area of Square
= 63.62 in² - 16 in².
= 47.62 in².
4.
Solution,
Given,
Area of the Square = 16 in².
Area of the Circle = 63.62 in².
Now,
The probability of landing in the Square = Square Area / Circle Area
= 16 / 63.62
= 0.25 .
5.
Solution,
Given,
White Part of the Circle = 47.62 in².
Area of the Circle = 63.62 in².
Now,
The probability of landing in the white Part = White Area / Circle Area.
= 47.62 / 63.62
= 0.74 .
Given the function g(x)=√x+4, which of the following values cannot be the domain of g?
A. X=1
B. X=2
C. X=12
D. X=-5
Answer:
D. x = -5
Step-by-step explanation:
The square root function is only defined for non-negative arguments. For the function ...
[tex]g(x)=\sqrt{x+4}[/tex]
this means we must have ...
x +4 ≥ 0
x ≥ -4 . . . . . . subtract 4 from both sides
All of the numbers on your answer choice list are more than -4 except -5.
x = -5 is not in the domain of g(x)
HELP PLEASE. Check picture. I have tried but cannot seem to get it.
Answer:
[tex]884^{-7}[/tex]
Step-by-step explanation:
Start by simplifying the denominator of the fraction. When multiplying exponents of the same base, you can add the exponents. This is also known as the product rule.
[tex]a^x\cdot a^y=a^{x+y}[/tex]
["a" is the base, and "x" and "y" are the exponents]
Using this we find...
[tex]884^{58}\cdot884^{46}=884^{58+46}=884^{104}[/tex]
When dividing exponents of the same base, you can subtract the exponents. This is also knows as the quotient rule.
[tex]a^x\div a^y=a^{x-y}[/tex]
Using this we find...
[tex]\frac{884^{97}}{884^{104}}=884^{97-104}=884^{-7}[/tex]
Answer:
[tex]884^{-7[/tex]
Step-by-step explanation:
≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡
Before we begin solving, let's review a few rules of exponents.
If an exponent is multiplying with another exponent and their bases are the same, you can simply add the exponents.If an exponent is dividing with another exponent and their bases are the same, you can simply subtract the exponents.≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡
⇒ [tex]\dfrac{884^{97} }{884^{58} \times 884^{46} }[/tex]⇒ [tex]\dfrac{884^{97} }{884^{58 + 46}}[/tex] [#1]⇒ [tex]\dfrac{884^{97} }{884^{104}}[/tex]⇒ [tex]884^{97 - 104[/tex] [#2]⇒ [tex]\boxed{884^{-7}}[/tex]≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡≡
Solve each inequality.
X+5 < 6
Pls help
Answer:
x<1
Step-by-step explanation:
You would just subtract 5 from both sides of the equation. The sign does not flip because you are not multiplying or dividing any negative number across the sign. So simply x+5 (-5) < 6 (-5). On the left side the 5 would cancel out. on the other side 6-5 is equal to 1.
Answer: x<1
Answer: x < 1
Step-by-step explanation: x + 5 < 6
Subtract 5 from both sides,
x < 1