1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Klio2033 [76]
3 years ago
8

By far the largest and most widespread use of americium-241 is as a component in household and industrial smoke detectors, where

a small amount is used in an ionization chamber inside the detector. The half life of americium-241 is 432.2 years. If a smoke detector is buried in a land fill, how many years are required for the original amount of americium-241 to decay to less than 1% of the original amount? Round your numerical answer to the nearest tenth of a year.
1,435.7 years


4,322 years


2,871.5 years


43,220 years
Mathematics
1 answer:
svlad2 [7]3 years ago
3 0
<h3>Answer:</h3>

2871.5 years

<h3>Step-by-step explanation:</h3>

The number of half-lives can be found by solving ...

... (1/2)^x = (1/100)

Taking logs, you have ...

... x·(-log(2)) = -log(100)

... x = log(100)/log(2) ≈ 6.64386

Then the number of years for the desired decay is ...

... (432.2)×6.64386 ≈ 2871.5 . . . . years

You might be interested in
Find the values for x and y.
vivado [14]
Both sides need to equal 180 (The side with the 90 degrees measurement and the side with equations). So first subtract 180 from 90
180 - 90
to get the measurement of 5x and you get 90 but we aren't done yet since we need to find x so now we need to divide 5 by 90
90 \div 5 = 18
and we get 18 which is X.
x = 18
Now we need to find the measurement of Y. Now both angles on that side together equals 180 so we need this equation.
5(y + 11) + 4y - 10 = 180
First, distribute 5(y + 11)
5 \times y \\ 5 \times 11
Then you get this equation :
5y + 55 + 4y - 10 = 180
Now, add the two equations together
5y + 55 + 4y - 10
and you get this equation

9y + 45 = 180
Now subtract 45 from both sides
9y + 45 - 45 = 180 - 45
and divide by 9 on both sides
9y \div 9 = 135 \div 9
and you get your answer
y = 15

So
x = 18
and
y = 15
8 0
3 years ago
What is the answer to 5x-10
IrinaVladis [17]
-50 hope this helped 
5 0
3 years ago
Find the distance between the two points rounding to the nearest tenth (if
lana [24]

Answer:

5.7

Step-by-step explanation:

Creating the point into a triangle, both sides a 4.

As the Pythagorean theorem goes, a^2+b^2=c^2

4^2+4^2=

16+16=

32

The square root of 32 is about 5.7

The distance between the points is about 5.7 units

6 0
3 years ago
He length of a rectangle is three times its width. The perimeter of the rectangle is at most 112 cm.
g100num [7]
The equation relating length to width
L = 3W
The inequality stating the boundaries of the perimeter
LW <= 112
When you plug in what L equals in the first equation into the second equation, you get
3W * W <= 112
evaluate
3W^2 <= 112
3W <= 4 \sqrt{7}
W <= \frac{4 \sqrt{7} }{3} cm
8 0
3 years ago
Read 2 more answers
PLEASE HELP!!! Find the equation , in the standard form of the line passing through the points (3,-4) and (5,1)
ExtremeBDS [4]
\bf \begin{array}{ccccccccc}&#10;&&x_1&&y_1&&x_2&&y_2\\&#10;%  (a,b)&#10;&&(~ 3 &,& -4~) &#10;%  (c,d)&#10;&&(~ 5 &,& 1~)&#10;\end{array}&#10;\\\\\\&#10;% slope  = m&#10;slope =  m\implies &#10;\cfrac{\stackrel{rise}{ y_2- y_1}}{\stackrel{run}{ x_2- x_1}}\implies \cfrac{1-(-4)}{5-3}\implies \cfrac{1+4}{5-3}\implies \cfrac{5}{2}&#10;\\\\\\&#10;% point-slope intercept&#10;\stackrel{\textit{point-slope form}}{y- y_1= m(x- x_1)}\implies y-(-4)=\cfrac{5}{2}(x-3)\implies y+4=\cfrac{5}{2}x-\cfrac{15}{2}

\bf y=\cfrac{5}{2}x-\cfrac{15}{2}-4\implies y=\cfrac{5}{2}x-\cfrac{23}{2}\impliedby &#10;\begin{array}{llll}&#10;\textit{now let's multiply both}\\&#10;\textit{sides by }\stackrel{LCD}{2}&#10;\end{array}&#10;\\\\\\&#10;2(y)=2\left( \cfrac{5}{2}x-\cfrac{23}{2} \right)\implies 2y=5x-23\implies \stackrel{standard~form}{-5x+2y=-23}&#10;\\\\\\&#10;\textit{and if we multiply both sides by -1}\qquad 5x-2y=23

side note:  multiplying by the LCD of both sides is just to get rid of the denominators
5 0
3 years ago
Other questions:
  • What is 6x1(3+1)? I am just wondering what the answer and break down will be.
    13·2 answers
  • I am terrible with geometry.
    11·1 answer
  • A single microvillus is a rod-like structure that is 1.0 μm in height. it has a hemispherical top approximately 0.1 μm in diamet
    9·1 answer
  • What is the following quotient? Sqrt 96/ Sqrt 8
    15·2 answers
  • WHOEVER ANSWERS RIGHT WILL GET BRAINLIST
    12·2 answers
  • What is 51/7 by 31/9 in simplest form
    11·2 answers
  • Tony checked out 4 books from the library. He returned the books 3 days late. The fine for late books is $0.05 a day for each bo
    10·2 answers
  • A 9 pound block of butter is delivered each morning to restaurant recipe for one pot of soup cause for 6 ounces of butter using
    11·2 answers
  • No need for explaining just direct answers plz
    13·1 answer
  • Between which two numbers does the square root of<br> 131 lies?
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!