Answer:
12.5% is left
Explanation:If the half-life of a reaction is 6 days. What percentage of material is left after 18 days?
18 days/6 days = 3 half lives
each half life you lose half the material
in 3 half lives you have (1/2)x (1/2) x (1/2) =1/8
1/8 =0.125 so 12.5% is left
