N=NOe^-kt
N=mass at time t
NO = initial mass
k= 0.1476
t= time, in days
We are asked to find the half-life, which means you want to find how long it will take for half of the substance to decay/disappear (depending on situation).
If we are looking for half-life, we can simply set N to half of NO (which we are given a value of 40grams for)
Therefore:
N = 20
NO = 40
plugging these values and the value given for k back into the equation you get:
20 = 40e^-0.1476(t)
We are looking for t, so we have to manipulate the formula to get t by itself on one side of the equation.
We can start by dividing 40 from both sides, and you get:
0.5 = e^-0.1476(t)
We have the exponential function "e".
To get rid of e, we can use natural log (ln)
if e^y=x then ln (x) = y
look back at our equation we can set
0.5 = x
-0.1476(t) = y
Rewriting it in natural log form:
ln (0.5) = -0.1476(t)
Plug in ln (0.5) on a calculator to find its value and we get:
-0.693147 = -0.1476(t)
*Note: normally, getting a negative value would suggest that we did something wrong, because you cannot have a negative value as your t (you cannot have negative days), but because there is a negative on both sides of the equation, they will cancel out in this case.
The last step is to simply divide both sides by -0.1476
therefore:
T = 4.696119
But it asks you for the answer to the nearest tenth (one place after decimal pt) so
T (half life) = 4.7 days
Hope that helps :)
Answer:
The chosen topic is not meant for use with this type of problem. Try the examples below.
2 = |3x|
−4/5x + 1/25 = 0
3x = 4 − x
Answer:
48 hops/minute
Step-by-step explanation:
12 hops/15 seconds * 60 seconds/1 minute = 720 hops/15 minutes
simplify: 48 hops/minute
The student that did more maths problems per minute is Diedra.
In order to determine which student did more maths problems per minute, the rate of each student has to be determined. Rate is the total questions solved divided by the time.
Rate = total questions / total time
Malcolm = 15 / 18 = 0.833 problems per minute
Diedra = 16/ 17 = 0.941 problems per minute
To learn more about rate, please check: brainly.com/question/9834403
Answer:
26.8cm²
Step-by-step explanation:
the area if a rectangle is 53.6cm^2.If the length is multiplied by four and the width is halved, the area would then be?
Area of rectangle = length x width
53.6 = 4L x 1/2 W
53.6 = 2L × W
Divide both sides by 2
L × W = 53.6 ÷ 2
New area = 26.8cm²
I hope this was helpful, please mark as brainliest
