Answer:
10.4 hours
Explanation:
Now from;
0.693/t1/2 = 2.303/t log (No/N)
t1/2= half life of the radioactive isotope
t = age of the radioactive isotope
No= Original amount of radioactive isotope
N= amount of radioactive isotope left after time t
Substituting values;
N = 0.0625No
0.693/2.6 = 2.303/t log (No/0.0625No)
0.693/2.6 = 2.303/t log (1/0.0625)
0.267 = 2.303/t * log 16
0.267 = 2.773/t
t = 2.773/0.267
t = 10.4 hours
