Answer:
1/8 of original sample.
Explanation:
Consider your final amount is 100 g.
After three half lives:
at 0 = 100 g
1 half life = 100/2 = 50 g
2 half life = 50/2 = 25 g
3 half life = 25/2 = 12.5 g
Know multiply the amount after three half lives with 8.
12.5 g × 8 = 100 g
So, after three half lives 1/8 of original sample is present.
