science
posted by Angie .
how old is a mammoth's tusk if there is only 25 percent C14 remaining in the sample?
a.5700 years
b.11400 years
c.17100 years
d.22800 years

Half disappeared in one halflife.
Half that remaining disappeared in the next halflife. 
..what does that mean?

Knowing the halflife of C14 would allow you to take twice the halflife.
From searching the Internet under "C14 half life", I found that the halflife of Carbon 14 is 5730 years.
This should help a little more. Thanks for asking. 
b.11400 years

B. 11400 years

5700
Respond to this Question
Similar Questions

Financial Analysis
Compute the present value of a $100 cash flow for the following combinations of discount rates and times: a. r = 8 percent. t = 10 years. b. r = 8 percent. t = 20 years. c. r = 4 percent. t = 10 years. d. r = 4 percent. t = 20 years 
Math
2x represents that Clyde is twice (2 times) as old as Bonnie. 6 years from now, Clyde will be twice as old as his cousin Bonnie will be then. If Clyde is now 16 years old, how many years old is Bonnie? 
finance
compute the present value of a $100 cash flow for the following combinations of discount rates and times. a. r=8 percent. t= 10 years b. r=8 percent. t= 20 years c. r=4 percent. t= 10 years d. r=4 percent. t= 20 years 
algebra
A person is 3 times as old as aonther person but in 15 years she will only be 2 times as old. I found the answer the younger person is 15 years old and the older person is 45 years old. But 15 years from now the younger person will … 
algebra
carbon 14 has a hlf life of 5700 years. scientists use this fact to determine the age of things made up of organic material. Suppose the average page of a book containing approximitly .5 mg og carbon 14 was put into a time capsule. … 
health
Children and adolescents are considered to be reflected in which age group? 
Math! Please check!
Which of the following is a good definition? 
Science
Can anyone help me find the halflife of strontium90? 
Geometry
Which statement is a good definition? You are a teenager if and only if you are 15 years old. You are not a teenager if and only if you are less than 13 years old. You are 13 to 19 years old if and only if you are a teenager. You are 
MATH HELP
Sam and Harry are family. Sam is currently is three times Harry's age. Sam's age is also 10 more than twice Harry's age. What are their current ages?