Question

The half life of a substance is 30 days. If there are 4.5 grams to start with, how much will be left after 23 days? Round to the nearest tenth of a gram. Be sure to label your answer.

Answer 1

65.4Step-by-step explanation:KHAN

Answer 2

Important formula:

$N_t = N_0 (1/2)^\frac{t}{t_{1/2}}$

Here, you are trying to find Nt and you have N0 = 4.5g, t = 23 days, t1/2 = 30 days. Plug the values in and you should get 2.7g left after 23 days.