A radioactive element has a half life of 4 days. The fraction that has decayed in 16 days is?
A
\(\frac{15}{16}\)
B
\(\frac{1}{16}\)
C
\(\frac{3}{4}\)
D
\(\frac{1}{4}\)
Verified Correct Answer: A.
Physical Principles & Numerical Solution
16 days = 4 half-lives.
The fraction left 16 days = after 4 half live, = (1/2)4 = (1)/16
Fraction that decayed = 1- \(\frac{1}{16}\)
\(\frac{15}{16}\)
Source: WAEC / JAMB / NECO Classroom Archive (Record #13891)