A(t) = Ao*e^(-rt)
-rt = ln [ A(t)/ Ao]
t = - ln [ A(t)/ Ao] / r
r= 0.0124% = 0.0124/100 = 0.000124
A(t)/A0 = 10% = 10/100 = 0.1
Now substitute
t = - ln [0.1] / 0.000124 = 2.3025851 / 0.000124 = 18,569 years
Your result will depend on how you round ln(0.1).
Answer:
DB = 6
Step-by-step explanation:
See the attached figure to the question.
Since O is the center of the given circle, so AB and CD are diameters of the circle.
Hence, AO = CO = OD = OB = radius of the circle = 6
In Δ OAC, we have AO = OC. Hence, ∠ A = ∠C = 60° {Given that ∠OAC = 60°}
So, ∠ AOC will automatically become 60°. {As the sum of all the angles of a triangle is 180°}
So, Δ AOC is equilateral triangle.
Now, ∠ AOC = ∠ BOD = 60° {Since, they are vertically opposite angles}
Now, in Δ BOD, we have DO = OB. Hence, ∠ D = ∠ B = 60° {As the sum of all the angles of a triangle is 180°}
So, Δ BOD is also an equilateral triangle.
So, DB = BO = DO = 6. (Answer)
It would be 3/2 x 3/1 which would = 4 1/2
Answer:
C. 5x
Step-by-step explanation:
So 72 pencils and 24 calculators
so greates number of identical calculators
this means
what is the biggest number that we can divide 72 and 24 by and get a whole number
this is called the GCM or greatest common multipule
to find the GCM, you factor 72 and group the like ones
72=2 times 2 times 2 times 3 times 3
24=2 times 2 times 2 times 3
so the common group is 2 times 2 times 2 times 3 or 24
so the greates number of packs is 24
so pencils
72 divided by 24=72/24=3
3 pencils per pack
24 divided by 24=24/24=1
1 calulator per pack
answer is 3 pencils and 1 calculator per pack