Answer:
14.99 hours
Step-by-step explanation:
The formula for half-life is given as,
R/R' = 2ᵃ/ᵇ...................... Equation 1
Where R= Original mass of sodium-24, R' = mass of Sodium-24 after disintegration, a = Total time taken for sodium-24 to disintegrate, b = half-life of sodiun-24.
Given: R = 1 kg, R' = 0.0156 kg, a = 90 hours
Substitute into equation 1 and solve for b
1/(0.0156) = 2⁹⁰/ᵇ
Taking the log of both side
log[1/(0.0156)] = log(2⁹⁰/ᵇ)
log[1/(0.0156)] = 90/b(log2)
90/b = log[1/(0.0156)]/log2
90/b = 6.0023
b = 90/6.0023
b = 14.99 hours
b = 14.99 hours.
Hence the half-life of Sodium-24 is 14.99 hours
Mike wants to paint one wall of his room. The wall measures 12 feet by 9 feet.on the wall is one square window that measures 4 1/2 feet on each side. Which of the following best describes the number of square feet Mike will paint? How much paint will Mike need?
Answer:
87.75 sq ft
Step-by-step explanation:
(12 × 9) - (4.5 × 4.5) = 87.75
prove this that the lll
Answer:
hmm pray you will fine the answer.
Step-by-step explanation:
dunno can you please say details
Can someone please show the answer and explain? tysm!
Answer:
B. 40°
Step-by-step explanation:
AB // ED ∠ABC = ∠EDF = 50°
AC // EF ∠AGE = ∠CAB = 90 - ∠ABC = 90 - 50 = 40°
What is the factored form of this expression?
x^2 + 6x − 16
Substitute numerical values into the expression for p and q.
Answer:
(x+2)(x-8)
Step-by-step explanation:
PLEASE HELP PLEASE HELP
NO EXPLANATION
Answer:
A hope it helped im a junior in college i dont take science
Step-by-step explanation:
Need help ASAP please
Answer:
because the length is 4 feet more than the width
=> the length is x + 4 (feet)
because the base has an area of 21 square feet
=> x(x + 4) = 21
<=> x² + 4x = 21
pls help me i am stuck on this question
Answer:
a. 25*17.5=437.5
b. 488
Step-by-step explanation:
a. If we put the two figures together they equal a square. so we do 25*17.5=437.5 if I'm wrong then try 875! Hope this helps
b. Lets add the rectangle and triangle together!!
32*10 +(8*32)/2
=320+256/2
=320+128
=488
Calculate each value for ⊙P. Use 3.14 for π and round to the nearest tenth.
mJKL = 230
area of shaded sector =
area of unshaded sector =
Answer:
Area of the unshaded sector = 113.4 sq units
Area of the shaded sector = 200.6 sq units
Step-by-step explanation:
First let us calculate the area of the circle
Area of the circle = πr²
radius r = 10units
Area of the circle = π(10)²
Area of the circle = π(100)
Area of the circle = 3.14(100)
Area of the circle = 314 sq. units
Area of a sector = theta/360 * πr²
Area of the unshaded sector = 130/360 * 314
Area of the unshaded sector = 13/36 * 314
Area of the unshaded sector = 113.389 sq units
Area of the unshaded sector = 113.4 sq units
Area of the shaded sector = Area of circle - Area of the unshaded sector
Area of the shaded sector = 314 - 113.89
Area of the shaded sector = 200.6sq. units
Can someone please help me for 4a. i know that answer and the answer is 15d+20 but what is the answer for the second part which is 4b.??
Answer:
I answered Part A here in your last question
https://brainly.com/question/23124193
B. No, you will not get a different amount because their expressions were the same, so they make the same ammount of money which is 1.3333 dollars per walk.
Step-by-step explanation:
If you have any quesitions feel free to ask in the comments
No Explanation Please Don't Answer
Answer:
A) [tex]\frac{1}{2}(9+15)w[/tex]
Step-by-step explanation:
Area of a trapezoid is [tex]\frac{1}{2}(base1+base2) *h[/tex]
[tex]A=\frac{1}{2}(9+15)*w[/tex]
Find the sum of the first 48 terms of the following series, to the nearest integer.
6, 9,12,...
6,9,12
Answer:
3,672
Step-by-step explanation:
Given the sequence 6, 9, 12...
The sequence is an arithmetic sequence
first term a = 6
common difference d = 9 - 6 = 12 - 9 = 3
number of terms n = 48
Sn = n/2[2a+(n-1)d]
Substitute the given values
S48 = 48/2[2(6)+(48-1)(3)]
S48 = 24(12+(3*47))
S48 = 24(12+141)
S48 = 24(153)
S48 = 3,672
Hence the sum of the first 48terms is 3,672
Solve the following systems: 3x+1=8y, 11y-3x=-11
Answer:
x= -10
y= -4
Step-by-step explanation:
Given data
3x+1=8y----------------1
11y-3x=-11--------------2
rearange
3x-8y=-1------------------1
-3x+11y=-11---------------2
add 1 and 2
3x-8y=-1------------------1
-3x+11y=-11---------------2
0+ 3y= -12
y= -12/3
y= -4
put y= -4 in 2
11y-3x=-11
11(-4)-3x=-11
-44-3x=-11
-44+11=3x
-33= 3x
x= -33/3
x= -10
Please help me with this
Answer:
55.56 Units
Step-by-step explanation:
6+10+13+6= 35.
LAST TIME TODAY BUT 5TH GRADE MATH
Answer: 1) 109.5 or 109 1.2
2) 136 r2
Step-by-step explanation:
Answer : 109 1/2 and 136 R 2
Step - by - step explanation :
First, convert the improper fraction into a mixed number . . . what is 438 divided by 4 ? 109.5 or 109 1/2 !
Second, divide . . . what is 1634 divided by 12 ? 136 with a remainder of 2 !
( sorry if any of these are wrong )
find the volume of a cone with a height 7 and radius 7
Answer:
359.19
Step-by-step explanation:
Using the formula V=(πr^2) * h/3 and plugging in the given values we get 359.19.
I estimated pi at about 3.14
I was in the hospital and missed a whole lesson in math HELP ME PLZZZ
Answer:
1.5 inches
Step-by-step explanation:
Area of a square:
A = a²
Given:
A = 2.25
Find a:
A = a²
2.25 = a²
[tex]\sqrt{a^2} =\sqrt{2.25}[/tex]
a = 1.5
I don't have a question just look at the picture
Answer:
I looked at the picture and it looks nice
Step-by-step explanation:
I dont know the answer?
946 x 1/3
Please help!!
Answer:
Sure! Your answer is about 315.33.
Step-by-step explanation:
If you want to figure this out by yourself, just open a calculator and do 946 * 0.33. You could also find this by dividing 946 by 3.
Please like and mark brainliest!
Hope it helps!
Find the area of a regular decagon with a perimeter of 60 ft.
Answer:
Area of a regular decagon with a perimeter of 60 ft. = 277 squared ft
Step-by-step explanation:
Decagon has 10 sides So 60/10 = 6 (each side = 6ft )
The sum of the interior angles of a decagon is 1 440 degrees.
There are 10 equal isosceles triangles of base angles 72 degrees in a decagon
Each isosceles triangle can subdivided into 2 right-angled triangles with height h and base length = (6/2) = 3 cm and base angle 72 degrees.
Height of right-angled triangle h = 3 tan 72 ft.
Area of 1 right-angled triangle = (1/2)(3)(3 tan 72) = 13.85 squared ft
Area of decagon = 20 right-angled triangles = 277 squared ft
A baker used 4 cups of flour to make 5
batches of cookies. He used _?_ of a
cup of flour to make lbatch of
cookies.
Answer:0.84
Step-by-step explanation:
Here,5 cups = 6 batches divided both side by 65/6 cups = 1 batches1 batch = 0.84 cupThus, 0.84 cups is required to make 1 batch of cookies.
In the problem y = 2x + 3
find y if x= 4.
Answer:
y = 11
Step-by-step explanation:
y = 2x + 3
so 2x is (2 multiplied by x)
so if x is 4, and we have 2x, we would do 2 x 4
2x4 is 8.
take the 3 from before and add that to 8
8+3 is 11.
so y = 11
Which of the following is a solution to the system of
equations?
4 + y = -x
y = 2x - 10
Answer:
x=3, y= -6
Step-by-step explanation:
make 4+y= -x as equation (1) and make y=2x-10 as equation (2, then you must find a third equation either from equation (1)or (2). If you choose to find equation (3) from (2) it will be y=2x-10 , then substitute equation (3) from (1) because you can't choose (2) , then it will be 4+(2x-10)= -x
the answer will be x =2
substitute x from equation (3)
y=2x-10
y=2 (2)-10
y= -6
(BRAINLYEST) Apply the markdown and find the sale price. Round to two decimal places when necessary.
A soft blanket originally cost $18.99. It is marked down 20%. What is the new price, not including sales tax?
Answer:
Got to quizlet it has the answer.
Step-by-step explanation:
Hope it helps
PLSSSSSSSSSS HHHELP MEE ITS A TESTTT
Answer:
The answer is C
Step-by-step explanation:
Which quantity is proportional to 35⁄80?
Answer:
7/16
Step-by-step explanation:
Answer:
7/16
Step-by-step explanation:
Simplify
gina drew three small congruent circles beside one large circle. based on the diagram which answer choice is the closest to the area of the large circle?
Answer:28.3 cm2
Step-by-step explanation:
Matt and Mark went to El Rodeo to have some dinner. Matt ordered 3 tacos and 2 enchiladas, which cost him $4.93. Mark ordered 2 tacos and 4 enchiladas, which cost him $6.38. What is the cost of one taco and what is the cost of one enchilada?
Answer:
The cost of one taco is $0.87 and the cost of one enchilada is $1.16
Step-by-step explanation:
Let the cost of tacos be X
and cost of enchiladas be y
So, by using given data, we have following equations
3X + 2Y = 4.93 (1)
2X + 4Y = 6.38 (2)
So, first multiply 1st equation by 2 and 2nd equation by 3, then subtracting 1st equation by 2nd.
= 2 × ( 3X + 2Y = 4.93) (1)
= 3 × (2X + 4Y = 6.38) (2)
= - (6X + 4Y = 9.86) (1)
= 6X + 12y = 19.14 (2)
= 8Y = 9.28
Y = 9.28 ÷ 8 = 1.16
By putting the value of Y in equation 1, we get
3X + 2(1.16) = 4.93
3X + 2.32 = 4.93
X = 2.61 ÷ 3 = 0.87
Hence, the cost of one taco is $0.87 and the cost of one enchilada is $1.16.
What is the slope-intercept form of the equation of the line with a slope of 1/4 that passes through (-4, -8)
Answer:
y=1/4x-7
Step-by-step explanation:
y-y1=m(x-x1)
y-(-8)=1/4(x-(-4))
y+8=1/4(x+4)
y=1/4x+4/4-8
y=1/4x+1-8
y=1/4x-7
in a race, a man covers 5km in 20 min. how much distance will he cover in 100 min
Step-by-step explanation:
men is covers by 25km in 100min
Find the volume of the prism. Round to the nearest tenth if necessary
Answer:
63cm³
Step-by-step explanation:
The shape above is a rectangular prism
The formula for a rectangular prism is given as:
= Length × Width × Height
Length = 3cm
Width = 3cm
Height = 7cm
= 3cm × 3cm × 7cm
= 63 cm³
The volume of the rectangular prism = 63cm³