Answer: The sample is 13414 years old.
Step-by-step explanation:
Expression for rate law for first order kinetics is given by:
[tex]t=\frac{2.303}{k}\log\frac{a}{a-x}[/tex]
where,
k = rate constant
t = age of sample
a = let initial amount of the reactant= 100
a - x = amount left after decay process= [tex]\frac{20}{100}\times 100=20[/tex]
a) for completion of half life:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
[tex]t_{\frac{1}{2}}=\frac{0.693}{k}[/tex]
[tex]k=\frac{0.693}{5730}=0.00012years^{-1}[/tex]
b) for completion of 20% of reaction
[tex]t=\frac{2.303}{0.00012}\log\frac{100}{20}[/tex]
[tex]t=13414years[/tex]
The sample is 13414 years old.
Answer: 13,307 years
Step-by-step explanation: i got it right on the quiz/asignment
Oliver is playing a math game. He chose three cards. The value of each card is shown.
First card -11. Second card 4. Third card -7 What is the sum of Oliver's three cards?
Answer:
1234567dgidchtdcjtdjutchitcbjtxvutx
least common multiple of 25 and 60
Answer:
300
Step-by-step explanation:
i multiplied to 300 thats the elast one PLEASE MARK BRAINLIEST
Find the LCD. 9, 12 The LCD is
please help and quick!!
Answer:
There is no such thing as LCD but I think you are trying to find LCM. LCM is least common multiple which is 36 because 9*4=36 and 12*3 also equals 36
Step-by-step explanation:
Answer:
36Step-by-step explanation:
Find prime factors of the given numbers
9 = 3*312 = 2*2*3Find the LCD
LCD(9, 12) = 3*3*2*2 = 36Wanda is making a border around her garden. She buys 9 bricks for her border. The bricks
weigh 27 kilograms in all.
How much does each brick weight
Answer:
3 kilograms...........
Answer:
27 ÷ 9 = 3
well , yeah , am i right ?
What is the domain of the relation
Answer:
0≤x≤3
Step-by-step explanation:
The domain is just all the possible values of x
we can see that the line goes through the x values 0 through 3
which means that
0≤x≤3
It's ≤ because it's a close circle
Can someone help me with this please?
what is a^2+15^2=17^2
I can't figure out what A is... HELP PLSSSSSSSSSSSSSSSSSSSSS
:3
Answer:
Step-by-step explanation:
Answer:
im bad at math sawy
Step-by-step explanation:
1.2.1
Question Help
An airplane on autopilot took 8 hours to travel 5,616 kilometers. What is the unit rate for kilometers per hour?
The unit rate is kilometer(s) per hour.
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2 + 6m + 7 = 57
pls show your work pls.
i need a full answer
Answer:
m=8
hope this helps
have a good day :)
Step-by-step explanation:
2 + 6m +7=57
9+6m=57 add like terms
6m=48 subtract 9 from each side
m=8 divide by 6 on each side
Answer:
M=8
Step-by-step explanation:
First your going to subtract 2 from 7 and thats 5.
then your going to do:
6m+5=57
Then subtract 5 from 57 and thats 52
and divide 52 from 6 and thats 8.
I suck at math ;-;
Answer:
50 mph
Step-by-step explanation:
We have the following point
(2,100)
We know that the equation has a y intercept of 0 which means our equation looks like this
y=mx
We know that when x=2 y=100 so
100=2m
m=50
50 mph
Answer:
It’s constant by 50 (1,50) (2,125) and so on
Step-by-step explanation:
25+25=50 75+50=125 and so on
multi-step equation
solve:
2p-3p-p=9-15-6
Answer:
p=-6
Step-by-step explanation:
2p-3p-p=9-15-6
or, -2p= -12
or, p= -12/-2
or, p= -6
2x = 3y + 2
y = -x +6
Answer:
x=4 and y=2
Step-by-step explanation:
2x=3(-x+6) +2
2x= -3x+18 +2
2x= -3x+20
5x=20
x=4
y=-(4) +6
y=2
2.
3. A brand of uncooked spaghetti comes in a box that is a rectangular prism
with a length of 9 inches, a width of 2 inches, and a height of 1 1/2
inches.
What is the surface area of the box? Explain.
There is a bag filled with 6 blue and 5 red marbles.
A marble is taken at random from the bag, the colour is noted and then it is replaced.
Another marble is taken at random.
What is the probability of getting 2 blues?
Answer:
25 of 121
Step-by-step explanation:
The correct answer is:
25 of 121
hegarty maths man told me so.
which value of x makes the equation 1.25(4 x-10)=7.5 true?
A. 3.5
B. -1
C. -0.5
D. 4
Answer:
4
Step-by-step explanation:
1.25(4x-10)=7.5
First step is to divide the 1.25 on both sides
4x-10 = 6
next step is to get x by itself by adding 10 to both sides
4x = 16
continue getting x by itself by dividing both sides by 4
x = 4.
calculate the total amount of milk in three cartons if each carton contains 236 ml of milk
Write equation of a line parallel or to a y=2x+3 that passes the ordered pair (3,6)
Answer:
y = 2x
Explanation:
To write the equation of a line u use the formula y = mx + b, where
y = y coordinate
m = slope
x = x coordinate
b = y intercept
One thing about parallel lines is that they always have the same slope. If you want to find a line parallel to y = 2x + 3, then the parallel line will also have a slope of 2.
So far, then, the equation would look like this: y = 2x + b
To find the y-intercept, we substitute in the values from (3,6) into the equation because the line passes through that point. So:
y = 2x + b
(6) = 2(3) + b
6 = 6 + b
6 - 6 = b
b = 0
Since the y-intercept is 0 (so the line passes through the origin), it doesn't need to be written on to the end of the equation.
y = 2x + 0 is just
y = 2x
That's your final equation! hope this helps!
Solve the equation
3s-4s=28
Answer:
-28
Step-by-step explanation:
Answer:
s=[tex]\frac{2}{3}[/tex]
Step-by-step explanation:
Solve for x in the following figure. Choose the appropriate result.
Answer:
d
Step-by-step explanation:
all of the angles add up to equal 180 so we setup the equation as 45+3x=180
first you subtract each side by 45
135=3x
then you divide each side by 3 and get that
x=45
Answer:
D, 45°
Step-by-step explanation:
at [tex]x=45[/tex]
the resulting angles would be [tex]45, 90, 45[/tex] and these add up to [tex]180[/tex]°
Identify a set of parallel lines and a set of perpendicular lines in this image
Answer
It is the first answer.
Step-by-step explanation:
Parallel lines are lines that will never cross each other.
Perpendicular lines are lines that cross each other at 90 degree angles (represented by the box in the corner).
A set of parallel lines and a set of perpendicular lines in this image are; AB║CD, CD ⊥ EF and AB ⊥ EF
How are parallel straight lines related?Parallel lines have the same slope since the slope is like a measure of steepness and since parallel lines are of the same steepness, thus, are of the same slope.
Since Parallel lines are lines that will never cross each other.
We know that Perpendicular lines are lines that cross each other at 90 degree angles.
The parallel lines are AB and CD, the perpendicular are AB and EF because the first sets are side by side and the second sets cross each other at a certain point.
Therefore the set of parallel lines and a set of perpendicular lines in this image are; AB║CD, CD ⊥ EF and AB ⊥ EF
Learn more about parallel lines here:
https://brainly.com/question/13857011
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Please help asap needed :)
Answer:
362.35N/m²
Step-by-step explanation:
Pressure = Force/Area
Area = πr²
Area = 3.14(0.75)²
Area = 3.14(0.5625)
Area = 1.76625m²
Force = 640N
Pressure = 640/1.76625
Pressure = 362.35N/m²
Which of the following objects show an OBTUSE angle?
Help please help help help:)
Answer:
1/8 of a pound
Step-by-step explanation:
(3/4) ÷ 6 = .125 = 1/8
Andrew collects coins. He collected a total of 275 coins. If 84% of the coins he collected were foreign, how many other coins did he collect? Andrew collected coins that were not foreign
Answer:
44
Step-by-step explanation:
1. Find out how many coins were foreign
x. 84
------ = ---------
275. 100
2. Subtract 231 (Foreign coins) by 275 (Total coins)
3. The answer is 44
The percentage is calculated by dividing the required value by the total value and multiplying by 100.
The number of foreign coins.
84% of 275 = 231
The number of foreign coins is 231.
What is a percentage?The percentage is calculated by dividing the required value by the total value and multiplying by 100.
Example:
Required percentage value = a
total value = b
Percentage = a/b x 100
Example:
50% = 50/100 = 1/2
25% = 25/100 = 1/4
20% = 20/100 = 1/5
10% = 10/100 = 1/10
We have,
Total number of coins = 275
Percentage of foreign coins = 84%
The number of foreign coins.
= 84% of 275
= 84/100 x 275
= 231
Thus,
The number of foreign coins is 231.
Learn more about percentages here:
https://brainly.com/question/11403063
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Can someone help me with this please???...
Answer:
2×2×2×2× 5
Step-by-step explanation:
use the tree method it helps
Answer:
hey mate this is your answer..
The sum of two numbers is 18 and their difference is 4 what are the two numbers?
Answer:
7 and 11
Step-by-step explanation:
Let the two numbers be x and y
x+y = 18
x-y = 4
Add the two equations together to eliminate y
x+y = 18
x-y = 4
----------------
2x +0y = 22
Divide each side by 2
2x/2 = 22/2
x = 11
Solve for y
x+y = 18
11+y =18
Subtract 11 from each side
11+y-11 =18-11
y = 7
The two numbers are 7 and 11
interest earned:? principal: 250$ interest rate: 4% time: 2 years
First begin with the interest formula.
Interest = Principal x Rate x Time
The $250 is the principal is the amount of money invested.
The rate is 4% which translates to the decimal .04.
The time is 5 years.
So we have I = (250)(.04)(2).
Multiplying, (25)(.04) is 10 and we have 10(2) which is 20.
This means that the interest earned in 2 years is $20.
Help me on this plsss
Answer:
tried my best 2 help
Step-by-step explanation:
2.circumference = pi x diameter
c = pi x (8x2)
c= 50.2654824574
3. when measuring physical objects,
4. to find the length around an object such as your waist when buying a top ???? couldnt think of anything else
please help again :,)) is it one solution, all solutions, or one
please show your work.
Answer:
Infinite many solutions
Step-by-step explanation:
If you graph it there is only 1 line
Write the equation of the line in slope intercept form that has a slope of -1/5 and contains (-5,-3)
Answer:
y = [tex]-\frac{1}{5}x[/tex] - 4
Step-by-step explanation:
As we know the point slope form of an equation is as follows -
y - y₁ = m ( x - x₁ )
As we have slope , m = [tex]-\frac{1}{5}[/tex]
And point (x₁ , y₁ ) = ( -5, -3)
⇒ y - ( -3) = [tex]-\frac{1}{5}[/tex] ( x - (-5) )
⇒ y + 3 = [tex]-\frac{1}{5}[/tex] ( x + 5 )
⇒ y + 3 = [tex]-\frac{1}{5}[/tex] x - 1
⇒ y = [tex]-\frac{1}{5}[/tex] x - 1 - 3
⇒ y = [tex]-\frac{1}{5}[/tex] x - 4
So, the equation becomes
y = [tex]-\frac{1}{5}x[/tex] - 4