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3 years ago

If a radioactive isotope has a half-life of 6 hours and 12 milligrams is initially present, how much will

Mathematics

1 answer:

Serhud [2]3 years ago

3 0

Answer:0.75 milligrams will be present in 24 hours

Step-by-step explanation:

Step 1

The formula for radioactive decay can be written as

N(t)=No (1/2)^(t/t 1/2)

where

No= The amount of the radioactive substance at time=0=milligrams

t 1/2= the half-life= 6 hours

t=24 hours

N(t) = the amount at time t

Step 2--- Solving

N(t)=No (1/2)^(t/t 1/2)

=N(t)=12 x ( 1/2) ^ (24/6)

= 12 x (1/2) ^4

= 12 x 0.0625

= 0.75 milligrams

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nikdorinn [45]

Answer:

I think that it should be

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Step-by-step explanation:

Here,

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we know that,

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I am done .

4 0

4 years ago

Read 2 more answers

Find the volume of the prism

Andrei [34K]

Answer:

440cm³

Step-by-step explanation:

Area of trapezium base=

$\frac{1}{2} \times (a + b) \times h$

$\frac{1}{2} \times (8 + 14) \times 4$

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3 years ago

Or which equation would x = 4 be a solution?

ElenaW [278]

$2x+7=22\ \ \ \ |-7\\2x=15\ \ \ \ \ |:2\\x=7.4\neq4\\----------------------\\6x\div8=3\ \ \ \ |\cdot8\\6x=24\ \ \ \ |:6\\x=4\\-------------------\\8-3x=20\ \ \ \ |-8\\-3x=12\ \ \ \ |:(-3)\\x=-4\neq4\\---------------------\\2x+8=4\ \ \ \ \ |-8\\2x=-4\ \ \ \ \ |:2\\x=-2\neq4\\\\Answer:\ 6x\div8=3$

Other method.

Enter the value of x for each equation and check the equality of the pages of the equation

$2x+7=22\\L=2(4)+7=8+7=15;\qquad R=22\qquad L\neq R\\\\6x\div8=3\\L=6(4)\div8=24\div8=3;\qquad R=3;\qquad L=R\\\\8-3x=20\\L=8-3(4)=8-12=-4;\qquad R=20;\qquad L\neq R\\\\2x+8=4\\L=2(4)+8=8+8=16;\qquad R=4;\qquad L\neq R$

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3 years ago

What is the area of the triangle shown below?

elena-s [515]

Answer:

5 un^2

Step-by-step explanation:

the liens from (0, 0) to (1, 3) and (1, 3) to (4, 2) are perpendicular meaning that the angle at (1, 3) is a right angle

to find the lengths of the sides we must use the pythagorean theorem

a^2 + b^2 = c^2

for the leftmost side

we have 1^2 + 3^2 = c^2

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c^2 = 10

c = sqrt(10)

for the top side

we have

the same thing

1^2 + 3^2 = c^2

1 + 9 = 10

c^2 = 10

c = sqrt(10)

you must multiple sqrt(10) by sqrt(10) and then by 1/2

sqrt(10) * sqrt(10) is 10

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the area is 5 un^2

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1 year ago

Choose the equation that represents the graph.

Pepsi [2]

Answer:

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Step-by-step explanation:

1) In this equation, -4 is the y-intercept (which is the point in the graph when x is 0 and y is something.)

2) Then, you have to check if the graph also has a y-intercept of -4 (it does)

3) Find out what the slope of the graph is. In this case, it is -2

4) If the equation also has a slope of -2 and y-intercept of -4, then it represents the graph.

Hope this helps :)

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3 years ago