Answer:
If you have a quantity X of a substance, with a decay constant r, then the equation that tells you the amount of substance that you have, at a time t, is:
C(t) = X*e^(-r*t)
Now, we know that:
We have 2000g of substance A, and it has a decay constant of 0.03 (i assume that is in 1/year because the question asks in years)
And we have 3000 grams of substance B, with a decay constant of 0.05.
Then the equations for both of them will be:
Ca = 2000g*e^(-0.03*t)
Cb = 3000g*e^(-0.05*t)
Where t is in years.
We want to find the value of t such that Ca = Cb.
So we need to solve:
2000g*e^(-0.03*t) = 3000g*e^(-0.05*t)
e^(-0.03*t) = (3/2)e^(-0.05*t)
e^(-0.03*t)/e^(-0.05*t) = 3/2
e^(t*(0.05 - 0.03)) = 3/2
e^(t*0.02) = 3/2
Now we can apply Ln(x) to both sides, and get:
Ln(e^(t*0.02)) = Ln(3/2)
t*0.02 = Ln(3/2)
t = Ln(3/2)/0.02 = 20.3
Then after 20.3 years, both substances will have the same mass.
Answer:
I would help you but can't see the picture maybe try posting it again
Answer:
Twelve less three times a number is at least nine.
Twelve minus the product of three and a number is no smaller than nine.
Step-by-step explanation:
complete question is:
Twelve less than three times a number is greater than or equal to nine.
Twelve less than three times a number is at least nine.
Twelve less three times a number is at least nine.
Twelve minus the product of three and a number is no more than nine.
Twelve minus the product of three and a number is no smaller than nine.
ANSWER:
<u>Twelve less three times a number is at least nine.</u>
The phrase "twelve less three..." means that the "three times a number" is being subtracted from twelve. So, it has to be at least nine.
<u>Twelve minus the product of three and a number is no smaller than nine.</u>
Even the least number you suppose is 1 we'll get 9
e.g: 12-3(1)=9. Therefore, this statement also represent the inequality
Answer: pretty sure its C.
Step-by-step explanation:
i know its not a or b but i dont know what d means so good luck
Answer:(-1,-2)
Step-by-step explanation:
