You would multiply the growth rate (.009) by 2/3 to get the percent rate per year. Therefore, the answer is .006
Answer:
see below
Step-by-step explanation:
The equation for half life is
n = no e ^ (-kt)
Where no is the initial amount of a substance , k is the constant of decay and t is the time
no = 9.8
1/2 of that amount is 4.9 so n = 4.9 and t = 100 years
4.9 = 9.8 e^ (-k 100)
Divide each side by 9.8
1/2 = e ^ -100k
Take the natural log of each side
ln(1/2) = ln(e^(-100k))
ln(1/2) = -100k
Divide each side by -100
-ln(.5)/100 = k
Our equation in years is
n = 9.8 e ^ (ln.5)/100 t)
Approximating ln(.5)/100 =-.006931472
n = 9.8 e^(-.006931472 t) when t is in years
Now changing to days
100 years = 100*365 days/year
36500 days
Substituting this in for t
4.9 = 9.8 e^ (-k 36500)
Take the natural log of each side
ln(1/2) = ln(e^(-36500k))
ln(1/2) = -36500k
Divide each side by -100
-ln(.5)/36500 = k
Our equation in years is
n = 9.8 e ^ (ln.5)/36500 d)
Approximating ln(.5)/365=-.00001899
n = 9.8 e^(-.00001899 d) when d is in days
Answer:
Julie can buy 4 plants
Step-by-step explanation:
A plant costs £6.80 and Julie has £30.
In order to find out how many plants she can buy with £30, we need to see how much times £6.80 can go into £30. In other words, we need to divide £30 by £6.80 so we get the number times it can go into £30. That will be the number of plants.
£30 ÷ £6.80 = 4.41176470588
Julie can't get 0.41176470588 of a plant so we have to round it to 4. She can buy 4 plants.
She has a bit of money left over (you can tell by the decimal number), but that isn't enough to buy another plant. So she buys 4 and has £2.80 left.
£6.80 x 4 = £27.20
Answer:
Step-by-step explanation:
Product means multiply
(10x^4y^2)(3xy3)
Numbers: 10*3 = 30
x: x^4 * x = x^5
y: y^2 * y ^3 = y ^ 5
Answer: 30x^5y^5
Powers don't multiply, they add. How confusing!
4 because 12 can be divide by 4 and 36 is also a multiple of 4.
12/4=3
4x9=36
Hope it helped!
-BFF2480
