Answer: 2500 years
Step-by-step explanation:
I'm not quite sure if I'm doing this right myself but I'll give it a shot.
We use this formula to find half-life but we can just plug in the numbers we know to find <em>t</em>.
![A(t)=A_{0}(1/2)^t^/^h](https://tex.z-dn.net/?f=A%28t%29%3DA_%7B0%7D%281%2F2%29%5Et%5E%2F%5Eh)
We know half-life is 5730 years and that the parchment has retained 74% of its Carbon-14. For
let's just assume that there are 100 original atoms of Carbon-14 and for A(t) let's assume there are 74 Carbon-14 atoms AFTER the amount of time has passed. That way, 74% of the C-14 still remains as 74/100 is 74%. Not quite sure how to explain it but I hope you get it. <em>h</em> is the last variable we need to know and it's just the half-life, which has been given to us already, 5730 years, so now we have this.
![74=100(1/2)^t^/^5^7^3^0](https://tex.z-dn.net/?f=74%3D100%281%2F2%29%5Et%5E%2F%5E5%5E7%5E3%5E0)
Now, solve. First, divide by 100.
![0.74=(0.5)^t^/^5^7^3^0](https://tex.z-dn.net/?f=0.74%3D%280.5%29%5Et%5E%2F%5E5%5E7%5E3%5E0)
Take the log of everything
![log(0.74)=\frac{t}{5730} log(0.5)](https://tex.z-dn.net/?f=log%280.74%29%3D%5Cfrac%7Bt%7D%7B5730%7D%20log%280.5%29)
Divide the entire equation by log (0.5) and multiply the entire equation by 5730 to isolate the <em>t</em> and get
![5730\frac{log(0.74)}{log(0.5)} =t](https://tex.z-dn.net/?f=5730%5Cfrac%7Blog%280.74%29%7D%7Blog%280.5%29%7D%20%3Dt)
Use your calculator to solve that giant mess for <em>t </em>and you'll get that <em>t</em> is roughly 2489.128182 years. Round that to the nearest hundred years, and you'll find the hopefully correct answer is 2500 years.
Really hope that all the equations that I wrote came out good and that that's right, this is definitely the longest answer I've ever written.
Answer:
I have placed it correct answers in the image above
Answer:
121.76
Step-by-step explanation:
the original price is 83.97. you would have to find 45% of that. you would do this by putting x/83.97= 45/100
multiply 45 and 83.97 to get 3778.65. then divide that by 100 to get 37.7865. Add that to 83.97 to get 121.7565. round it to the nearest hundreth to get the total of 121.76 dollars
mark as brainlyest and answer my question
Answer:
um no problem with this is easy
Well the 2 in the tens place is ten times as many as the 2 in the hundreds place.Also the 5 in the thousand place is 10 times as many as the 5 in the ten thousand place