Answer:
16.07 milligrams
Step-by-step explanation:
From the question,
Using the formula of radioactive decay,
R/R' = 2ᵃ/ᵇ..................... Equation 1
Where R = Original mass of the polonium-210, R' = Final mass of polonium-210 after decaying, a = Total disintegration time, b = half life of polonium-210.
Make R' the subject of the equation
R' = R/(2ᵃ/ᵇ)................ Equation 2
Given: R = 100 milligrams, a = 1 years = 365 days, b = 138.39 days
Substitute these values into equation 2
R' = 100/(2³⁶⁵⁰⁰/¹³⁸³⁹)
R' = 100/(6.222)
R' = 16.07 milligrams of plonium-210
x^2 + 4x − 9 = 0
I have no idea what to do! Help
Answer:
X= 1.8
Step-by-step explanation:
If I’m not mistaken then this is how to work it out. X^2 + 4x -9 =0. X^2 + 4x would be 5x. 5x - 9 = 0. +9 on both sides. 5x=9. Divide by 5 on each side. X= 1.8
There are 45 rows of tomato plants in the hydroponics farm at O'Brien's Farms Each row has 14 plants. 2/3 of the plants have sprouted. How many sprouted plants does O'Brien's have?
Answer: 420 sprouted plants
Step-by-step explanation:
First find the total number of tomato plants in the farm.
= Number of rows * No. of plants per row
= 45 * 14
= 630 plants
2/3 of them have sprouted so the number of sprouted plants is:
= 2/3 * 630
= 420 sprouted plants
PLEASE HELP RIGHT NOW ASAP IF CORRECT I WILL GIVE BRAINLIEST HELP NOW
Answer:
x^4
is the answer
ASAP someone please answer whether these numbers are irrational or rational and explain.
Answer:
are you lonly
Step-by-step explanation:
Answer:
vvv ahah hopefully it helps
Step-by-step explanation:
11. pi is irrational number since you can't write it down as a non-infinite decimal
12. .5 is rational since its a terminating decimal
13. .3 repeating is rational b/c it's represented as a ratio of two integers
Graph the line with the equation y = 1/2x+3
Answer:
(0,3) (-6,0) these will be the points
Which expression represents the sum of (2x - 5y) and (x + 2y)?
Answer:
B. 3x-3y
Step-by-step explanation:
Answer:
(A) 3x - 4y
Step-by-step explanation:
Avery invested $21,000 in an account paying an interest rate of 3.3% compounded continuously. Assuming no deposits or withdrawals are made, how long would it take, to the nearest year, for the value of the account to reach $29,200?
Answer:
10
Step-by-step explanation:
Answer from delta math
What is0.4¯ expressed as a fraction in simplest form?
Answer:
4 as a fraction is 2/5. Here you can submit another decimal number for us to convert to a fraction. Check out the next decimal number on our list that we converted to a fraction.
Step-by-step explanation:
pls mark me brainless to feed my frogs
Answer:
2/5
Step-by-step explanation:
ANSWER FOR BRAINLIEST:
The low temperatures for the last five days are: Low Temperatures: 62, 46, 50, 52, 55.
Find the MEAN ABSOLUTE DEVIATION (MAD) of the temperatures
Sample size:5
Mean: 53
Mean Absolute Deviation (MAD): 4.4
A glass jar contains a total of 53 marbles. The jar has red, blue, and green marbles. There are 3 blue marbles, 6 green marbles, and
the rest are red. Determine which event is likely
OA. Picking a green marble
OB. Picking a blue marble
OC. Picking a red marble
OD. Picking a yellow marble
Answer:
c. picking a red marble.
Answer:
Picking a red marble. C.
Step-by-step explanation:
helppp please, i don’t know how to do this
Answer:
Line CB
Step-by-step explanation:
We know the smallest triangle is the left triangle, so you need to find the smallest angle in that triangle, which is 50 degrees as shown, and the opposite side to that, CB, is the smallest side.
find the distance between the two points rounding to the nearest tenth (1,9) (-2,6)
Answer:
3sqrt2 is the distance between these two points
A box of cereal is halfway full. How much cereal is in the box? 14 in 2 in 8.8 in
Answer:
I'm honestly proud of myself for getting this right, the answer is 123.2
Step-by-step explanation:
14 x 8.8 x 2 divides by 2 and that's your answer pretty self-explanatory and simple
Represent 0.533 (only the last 3 is bar number) into a rational number
Answer:
[tex]\frac{8}{15}[/tex]
Step-by-step explanation:
We require 2 equations with the repeating 3 placed after the decimal point.
let x = 0.5333.. ( multiply both sides by 10 and 100 )
10x = 5.333... → (1)
100x = 53.333... → (2)
Subtract (1) from (2) tus eliminating the repeating 3
90x = 48 ( divide both sides by 90 )
x = [tex]\frac{48}{90}[/tex] = [tex]\frac{8}{15}[/tex]
Answer:
IT IS 8/15
Step-by-step explanation: Divide and multiply the fraction from 100 to tens
help me with this math question gr 8 math please
Answer:
C = 112, A = 150, D = 30, B = 38
Step-by-step explanation:
I solved C first using:
30+38+c = 180 (angles along a straight line should add up to 180 since a whole circle is 360)
-
I solved A by looking across from C.
Angles on opposite sides should mirror each other but A includes 38* + C
Just by doing 112 + 38 you get 150.
-
I solved D by looking at 30*, alternative interior angles are the same so D is 30*.
-
I solved B by taking C (112) and D (30) and adding them together and subtracting from 180.
Interior angles of a triangle should all add up to 180,
112 + 30 + B = 180
From this I got that B was 38.
Alternatively you can find this out by looking at the 38 degrees, corresponding congruent angles are always the same.
I suggest reviewing this angles sheet if you're ever stuck in the future.
Answer:
C = 112, A = 150, D = 30, B = 38
Step-by-step explanation:
Leticia went into Discount Music to price CDs. All CDs were discounted 23% off the marked price. Leticia wanted to program her calculator so she could input the marked price and the discounted price would be the output. Which of the following is an expression for the discounted price on a marked price of p dollars?
p – 0.23p
p – 0.23 p
p – 0.23
p – 0.23
p – 23p
p – 23 p
p – 23
p – 23
0.23p
Answer:
0.23p
Step-by-step explanation:
23% is 0.23 in decimal form. To get the discount amount you have to multiple 0.23 times the dollar amount of the CDs. Or multiply it to p
A geologist drew a scale drawing of a section of a quartz layer she saw in a cliff. The scale drawing of the layer is 4 cm high and 28 cm long. If the actual layer is 0.2 meters high, what is the area of the actual quartz layer section she saw?
Answer:
[tex]0.28\ \text{m}^2[/tex]
Step-by-step explanation:
[tex]4\ \text{cm}=0.2\ \text{m}[/tex]
[tex]1\ \text{cm}=\dfrac{0.2}{4}=0.05\ \text{m}[/tex]
[tex]28\ \text{cm}=28\times 0.05=1.4\ \text{m}[/tex]
The height of the layer is 0.2 m and the length is 1.4 m
Area is given by
[tex]0.2\times 1.4=0.28\ \text{m}^2[/tex]
Area of the actual quartz layer section is [tex]0.28\ \text{m}^2[/tex].
If you continually experience budget defi-
cits, how can you decide which expenses
to cut?
Answer:
you need to cut variable expenses first
Caitlyn earned $25 at work yesterday. She now has $60.
How much money did Caitlyn have before earning $25 at work?
Answer:
$35
Step-by-step explanation:
60 - 25 = 35
Answer:
$35
Step-by-step explanation:
60-25= $35
you good bro????
Classify the triangles shown below as "scalene," "isosceles," or "equilateral." Sides that are the same length are marked with a slash. Write the letter of each triangle and the category or categories in which it belongs. If a triangle fits more than one classification, write all categories that apply.
A box contains 2 purple marbles, 2 blue marbles, 3 green marbles, and 5 red marbles. 2 purple marbles, 2 blue marbles, 3 green marbles, and 5 red marbles. Which color marble is most likely to be picked?
Answer:
A red marble
Step-by-step explanation:
First, add all of the possible combinations of marbles that can be picked from the box ( 2 + 2 + 3 + 5 = 12 ). Next, write down the amount of each marble ( 2 purple marbles, 2 blue marbles, 3 green marbles, and 5 red marbles). Then, find the marble that appears most in the box. (red marble). Finally, not only have you found that the red marble is most likely to be picked, you also know the probability of picking a red marble, (5/12).
Answer: red
Step-by-step explanation:
help ME pls
.............
Answer:
not sure how this is math
Answer:
Keep your head up king/queen
40-40x0+1 find PEMDAS
P - Parentheses
E - Exponents
M - Multiply
D - Divide
A - Add
S - Subtract
PEMDAS, is just an order of operations...
In our order above, Multiplying comes BEFORE addition OR Subtraction...
40 x 0 = 0
Then moving to the front...
40 - 0 = 40...
Lastly, 40 + 1 = 41
Answer is 41
answer this question for brainilest and 20 points
Answer:
x = 5, y = 4
Step-by-step explanation:
Solve for one variable. x will be simpler using the second equation.
3x = 15
Divide by 3.
x = 5.
Now put that into the other equation.
4x + 5y = 40
Substitute variable.
4(5) + 5y = 40
20 + 5y = 40
Subtract 20 from both sides.
5y = 20
Divide by 5.
y = 4.
What the Sum of Adding the Polynomials.
Three students wrote a relationship between decimal, fraction, and percent's. Which of the students wrote an equivalent relationship? Lori wrote: 75% = 3/5 Talisha wrote: 0.05 = 50% Shannon wrote: 3/8 = 0.375
Answer:tyeydStep-by-step dh:
ghe
Shawna noticed that the distance from her house to the ocean which is 40 miles was one fifth the distance from her house to the mountains. Write and solve a division equation to find the distance from Shawna's house to the mountains.
Answer:
40 ÷[tex]\frac{1}{5}[/tex] =
40 x 5 = 200 miles
Step-by-step explanation:
distance from Shawna's house to the mountains = distance from her house to the ocean ÷ 1/5
40 ÷ 1/5
40 x 5 = 200 miles
Find the measure of XCY. PLEASE HELP ME AND SHOW WORK
Answer:
Measure of angle XCY is 60°.
Step-by-step explanation:
"Measure of all inscribed angles by the same arc in one segment of the circle are equal"
Using this property in the given circle,
m∠XWY = m∠XCY
60x = 61x - 1
61x - 60x = 1
x = 1
By substituting the value of 'x' in the measure of ∠XCY,
m∠XCY = 61x - 1
= 61(1) - 1
= 61 - 1
= 60°
Therefore, measure of angle XCY is 60°.
Sam ordered 7/8 of a pound of coffee. He would like to share half of it. How many pounds of coffee will each person receive?
Answer:
Sam and his friend will each get 7/16 of a pound of coffee
Step-by-step explanation:
7/8 × 1/2 = 7/16
What is the measure of the missing angle?
35°
105°
Answer:
Answer: 40 degrees
Step-by-step explanation:
If this is a triangle the missing angle would be 40 degrees because
35 + 105 + 40 = 180
Hope this helps!