The half-life of a certain radioactive element is 35 hours. If there are 904 grams of this element, how much will be left after 70 hours? (please help I might fail Math.)

Answers

Answer 1

Answer:

226 grams

Step-by-step explanation:

The half-life of a radioactive substance is the time taken for half the quantity of the substance to decay such that the amount life after the given period of time is half the original quantity.

As such, given that the half-life of a certain radioactive element is 35 hours and there are 904 grams available, it means that after 35 hours,

Amount decayed = 1/2 * 904 grams

= 452 grams

Amount left = 904 grams - 452 grams

= 452 grams

After another 35 hours (now a total of 70 hours),

Amount decayed = 1/2 * 452 grams

= 226 grams

Amount left = 452 grams - 226 grams

= 226 grams


Related Questions

please help me it is math

Answers

Answer:

C is face

B is edge

A is vertex (where 2 or more points meet)

a rectangular field has side lengths that measure 9/10 mile and 1/2 mile what is the area of the field

Answers

Answer:

[tex]\frac{9}{20}miles^2=0.45miles^2[/tex]

Step-by-step explanation:

To find the area of a rectangle:

[tex]a=l*w[/tex]

where [tex]l[/tex] is the length and [tex]w[/tex] is the width.

In this case:

length: [tex]l=\frac{9}{10}miles[/tex]

width: [tex]w=\frac{1}{2} miles[/tex]

thus, we multiply this quantities to find the area:

[tex]a=(\frac{9}{10} miles)(\frac{1}{2}miles )\\\\a=\frac{9*1}{10*2}miles^2\\ \\a=\frac{9}{20}miles^2[/tex]

the area of this rectangle is 9/20 miles squared, or what is the same 0.45 miles squared

Divide and answer in simplest form: 4/5 ÷ 2

Answers

Answer:

2/5

Step-by-step explanation:

4/5*1/2=4/10=2/5

Answer:

0.4 or [tex]\frac{2}{5}[/tex]

Step-by-step explanation:

First convert 4/5 into a decimal of 0.8

Then divide 0.8 by 2 which gives you 0.4 or [tex]\frac{2}{5}[/tex]

Use the distance formula to write an equation of the parabola with focus F(0, -13) and directrix y=13

y=?

(FINALEXAM)

Answers

Answer:

-1/52 x^2

Step-by-step explanation:

4p(y-k)=(x-h)^2

4(-13)y=x^2

-52y=x^2

y=-1/52 x^2

what is the equation of the line passing through ( -5, -3 ) and perpendicular
to the line representing the equation y = - 5/7x + 2?

Answers

Answer:

y = 7/5x + 4

Step-by-step explanation:

use the slope from the equation -5/7 and take the negative reciprocal to get the perpendicular slope = 7/5. Then use the equation y=mx+b. Plug in x and y from the point given and the new slope and solve for b.

(-3) = (7/5)(-5) + b, (-3) = -7 + b, add 7 to both sides. b = 4. Rewrite the equation now to be y = 7/5x + 4

The ordered pair below is a solution to which equation?
(5,40)

Answers

Answer:

y = 8x

Step-by-step explanation:

a  y = 8x

 40 = 8*5

 40 = 40

This is a solution

Find the solutions for a triangle with a = 16, c =12, and B = 63º.

a. A = 71.6°; C = 52.89; b =12.0

C. A = 68.6° C = 45.40; b=12.0

b. A = 71.6°; C = 45.40; b =15.0

d. A = 68.6°; C = 52.89; b=15.0

Answers

Answer:

b. A = 71.6°; C = 45.40°; b =15.0

Step-by-step explanation:

The missing values can be found with the help of the Law of Cosine and properties of triangles:

Side b (Law of Cosine)

[tex]b = \sqrt{a^{2}+c^{2}-2\cdot a \cdot c \cdot \cos B}[/tex]

[tex]b = \sqrt{16^{2}+12^{2}-2\cdot (16)\cdot (12) \cdot \cos 63^{\circ}}[/tex]

[tex]b \approx 15.022[/tex]

Angle A (Law of Cosine)

[tex]\cos A = -\frac{a^{2} - b^{2}-c^{2}}{2\cdot b \cdot c}[/tex]

[tex]\cos A = - \frac{16^{2}-15.022^{2}-12^{2}}{2\cdot (15.022)\cdot (12)}[/tex]

[tex]\cos A = 0.315[/tex]

[tex]A= \cos^{-1} 0.315[/tex]

[tex]A \approx 71.639^{\circ}[/tex]

Angle C (Sum of internal angles in triangles)

[tex]C = 180^{\circ} - 63^{\circ} - 71.639^{\circ}[/tex]

[tex]C = 45.361^{\circ}[/tex]

Hence, the right answer is B.

Plz can someone help

Answers

Answer:

the total number of students is 1240

Step-by-step explanation:

the difference between 11 and 9 is 2

124÷2=62

62×11=682

62×9=558

682+558=1240

pls give me brainliest!

What is 19 percent of 50​

Answers

Answer:

What is 19 percent (calculated percentage %) of number 50? Answer: 9.5.

Step-by-step explanation:

Answer:

9.5

Step-by-step explanation:

19% of 50

Convert the percentage to a decimal.

19% = 0.19

Multiply the decimal by the number.

50 × 0.19 = 9.5

9.5 is the answer.

At the end of the school year a school system has a table with the total absences and tardies in its 10 schools what is the best way to display these data?

A. Bar Graph
B.Circle Graph
C. Stem and leaf plot
D.Ogive graph

Answers

Answer:

A

Step-by-step explanation:

The probability of not choosing a black shirt is...? please explain!

Answers

Answer:

80% or 8/10.

Step-by-step explanation:

Assuming the shirts in the bottom right are the "black" shirts, there is ten total shirts (1 red, 4 blue, 2 green, 1 white,  2 black.) Out of the ten shirts, 8 are not black. This means that there is an 80% chance that you will select a shirt that is NOT black.

The probability of not choosing a black shirt is 8/10. Because there is 10 shirts and 8 are not black.

Select the equivalent expression.
(2^-4 x z^-3)^5 =
Choose 1 answer:

Answers

Answer:

A

Step-by-step explanation:

[tex](2^{-4}z^{-3})^{5}[/tex]

several ways to approach this.

use power rule.  [tex](a^{m} )^{n} = a^{mn}[/tex]

[tex](2^{(-4*5)}z^{(-3*5)} )[/tex]

[tex](2^{-20} z^{-15} )[/tex]

RULE:  [tex]x^{-1} = \frac{1}{x}[/tex]

[tex]\frac{1}{(2^{20}z^{15}) }[/tex]

Solve.
-6x^2 - 2 - 3x=-8
a)x=5+√57÷16
b)x=-4+√34÷3
c)x=-7+3√41÷16
d)x=1+√17÷-4​

Answers

Answer:

So the d) is right.

Step-by-step explanation:

we have:

-6x^2 - 2 - 3x=-8

6x^2 + 3x - 6 =0

The delta = 3^2 -4*6*(-6) = 9 + 144 = 153= 9*17

These 2 solutions are:

[tex]x_{1} =\frac{-3+3\sqrt{17} }{2*6} = \frac{-3+3\sqrt{17} }{12} =\frac{-1+\sqrt{17} }{4} \\x_{2} =\frac{-3-3\sqrt{17} }{2*6} = \frac{-3-3\sqrt{17} }{12} =\frac{-1-\sqrt{17} }{4}[/tex]

So the d) is right.

Which of the following shows the correct simplification assuming the denominator is not equal to zero?

Answers

Answer:

[tex]=\frac{3x+2}{x\left(x+1\right)}[/tex]

or

[tex]\frac{(3x+2)}{x^2+x}[/tex]

Step-by-step explanation:

[tex]\frac{2}{x}+\frac{1}{x+1}\\\mathrm{Least\:Common\:Multiplier\:of\:}x,\:x+1:\quad x\left(x+1\right)\\Adjust\:Fractions\:based\:on\:the\:LCM\\Multiply\:each\:numerator\:by\:the\:same\:amount\:needed\:to\:multiply\:its\\\mathrm{corresponding\:denominator\:to\:turn\:it\:into\:the\:LCM}\:x\left(x+1\right)\\\mathrm{For}\:\frac{2}{x}:\:\mathrm{multiply\:the\:denominator\:and\:numerator\:by\:}\:x+1\\\frac{2}{x}=\frac{2\left(x+1\right)}{x\left(x+1\right)}\\[/tex]

[tex]\mathrm{For}\:\frac{1}{x+1}:\:\mathrm{multiply\:the\:denominator\:and\:numerator\:by\:}\:x\\\frac{1}{x+1}=\frac{1\cdot \:x}{\left(x+1\right)x}=\frac{x}{x\left(x+1\right)}\\=\frac{2\left(x+1\right)}{x\left(x+1\right)}+\frac{x}{x\left(x+1\right)}\\\mathrm{Since\:the\:denominators\:are\:equal,\:combine\:the\:fractions}:\quad \frac{a}{c}\pm \frac{b}{c}=\frac{a\pm \:b}{c}\\=\frac{2\left(x+1\right)+x}{x\left(x+1\right)}\\[/tex]

[tex]\mathrm{Expand}\:2\left(x+1\right)+x:\quad 3x+2\\2\left(x+1\right)+x\\\mathrm{Apply\:the\:distributive\:law}:\quad \:a\left(b+c\right)=ab+ac\\a=2,\:b=x,\:c=1\\=2x+2\cdot \:1\\\mathrm{Multiply\:the\:numbers:}\:2\cdot \:1=2\\=2x+2\\\mathrm{Simplify}\:2x+2+x:\quad 3x+2\\2x+2+x\\\mathrm{Group\:like\:terms}\\=2x+x+2\\\\mathrm{Add\:similar\:elements:}\:2x+x=3x\\=3x+2\\=\frac{3x+2}{x\left(x+1\right)}[/tex]

top side is 6 just couldn’t fit in picture

Answers

Answer: [tex]6<z<18[/tex]

Step-by-step explanation:

Use the pythagorean theorem to find z first.

[tex]c^2=a^2+b^2\\c=\sqrt{a^2+b^2}[/tex]

a = 12

b = 6

c = z

[tex]c=\sqrt{(12)^2+(6)^2}\\ c=\sqrt{144+36}\\ c=\sqrt{180} \\c=13.4[/tex]

z is greater than a and b

Which of these are NOT expressions?
Check all that are true.

123

9 + 3 = 12

3(4x + 5)

6 − 5 − 4 = z

3z + 2x


HELP

Answers

Answer:

6-5-4=z

9+3=12

Step-by-step explanation:

Expressions has no equal sign

“9 + 3 = 12” and “3(4x + 5)”

HELP ME QUICK PLZ WITH THIS MATH PROBLEM!!!!!!!!!!!!!!

Answers

Answer:

I believe it’s 1/2

Step-by-step explanation:

Take a point on the graph and use rise over run method

Answer:

D. 5/8 pounds

Step-by-step explanation:

You can find the slope by picking a point such as (8,5).

Slope = rise over run.

(8,5) is 8 units right and 5 units up, thus the slope is 5/8

Hope this helps.

hi what is the answer to c

Answers

I believe it should be 0.6mi/ m. Because 30/50=0.6

This graph shows a proportional relationship. (2/3, 3/4)


What is the constant of proportionality?

Answers

Answer: Hi! I'd love to help you but I'd need to see the graph.

Step-by-step explanation: Can you add a picture?

Mariana picked x apples at an orchard. She and her friends ate 6 of them, leaving 36 apples.
The number of apples can be represented by the equation 2 – 6 = 36. Plot a point on the
number line to represent x, the number of apples Mariana picked.
39
40
43
41
42.
44
36
37
38
32
31
33
35
30
34

Answers

42 is the answer because 36 + 6= 42

Drag the tiles to the correct boxes to complete the pairs.
Match each quadratic equation with its roots.

Answers

Answer:

Step-by-step explanation:

If the probability of a chance event is 0.67, it is less likely to happen
than which of the following probabilities of another chance event?
Select one:

0.76

0.61

0.65

0

Answers

Answer:

.76

Step-by-step explanation:

Does 10 24 26 make a right triangle

Answers

Answer:

Yes

Step-by-step explanation:

Answer:

no

Step-by-step explanation:

i can only assume you mean degrees, you worded it strangely, but they add to 60 degrees and a right triangle is 90

For this Prism to be a right prism, all the lateral faces must be rectangles. Is enough infromation given to prove the lateral faces are rectangles? Why or why not?

Answers

Answer:

No, there isn't enough information to prove that the lateral faces are rectangles

Step-by-step explanation:

i’ll give 17 points for this!

Answers

Answer:

90

Step-by-step explanation:

Answer:

90

Step-by-step explanation:

The reason why it is 90 because it looks like it is going in order so it would be 55 , 90 , 92 , 114

Hope i was to explain this real good Hope this is rightBrainliest plz

Determine the value of
X in the diagram below. Justify your reasoning.

Answers

Answer:

x = 70°

Step-by-step explanation:

Sum of external angles of polygon = 360

x + 150 + 140 = 360

x + 290 = 360

x = 360 - 290

x = 70°

Which three-dimensional figures have lateral faces that are polygons? Check all that apply. cones cylinders hemispheres prisms pyramids spheres

Answers

Answer:

Prisms

Pyramids

Step-by-step explanation:

Lateral faces of a pyramid are triangles (3 sided polygon)

Lateral faces of prisms are rectangles (4 sides polygon)

Answer:

Cylinders, Prisms, Pyramids

Step-by-step explanation:

Hope this helps

Brainliest if correct pls

Given the exponential equation y=34(5)x, what is the y-intercept (or starting point) of the graph?

Answers

Answer:

34

Step-by-step explanation:

Given

y = 34[tex](5)^{x}[/tex]

To find the y- intercept let x = 0, that is

y = 34[tex](5)^{0}[/tex] = 34 × 1 = 34 ← y- intercept

Yes the answer is 34 because if you

Which number is equal to 10 Superscript 4?
40
1,000
10,000
40,000

Answers

Answer: The answer is 10,000

Step-by-step explanation:

10^4 is equal to 10,000

10^4 to the second power means that you have too add 4 zeros to the end of the number.

Since 10 already has a 0, you would add 3 more.

Therefore, the answer would be 10,000.

(Your Welcome)

Answer:

10^4 is equal to 10,000

10^4 to the second power means that you have too add 4 zeros to the end of the number.

Since 10 already has a 0, you would add 3 more.

Therefore, the answer would be 10,000.

THIS IS NOT A QUESTION!
This is a list of Area and Perimeter on the coordinate plane answers from Khan Academy.

approximate perimeter of STRIPE is 36.01

area of rectangle TOUR is 80

perimeter of of polygon CHOMP is 32.52

area of parallelogram YORK is 122

the area of trapezoid MASK is 34

The approximate perimeter of polygon CODIFY is 51.53

The area of triangle SOL is 52

The approximate perimeter of polygon DINGO is 34.44

the approximate perimeter of the isosceles triangle PAZ is 20.03

the area of triangle CAW is 10

The approximate perimeter of rectangle PEAR is 34.99

The area of trapezoid COWL is 45

The area of triangle TOP is 87/2 units

The approximate perimeter of triangle VEN is 29.80

The area of parallelogram TOWN is 40

the approximate perimeter of quadrilateral BOAT is 30.34

Answers

Omg! Thank you. I was stuck for like an hour till I found this.

Answer:

Omg, thank you so much

Step-by-step explanation:

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