Question

Fritz is recording the decay of radioactive material. The table displays the

number of weeks and the level of radioactivity he measures each week.
What will be the level of radioactivity in 10 weeks?

Answer 1

Every week, the radioactivity decreases by a factor of 5

After 1 week, it goes from 5,000 to 1,000

2 weeks 1,000 / 5 =200

3 weeks 200 / 5 = 40

4 weeks 40 / 5 = 8

5 weeks 8 / 5 = 1.6

6 weeks 1.6 / 5 = 0.064

7 weeks 0.064 / 5 = 0.0128

8 weeks .0128 / 5 = 0.00256

9 weeks 0.00256 / 5 = 0.000512

10 weeks 0.000512 / 5 = 0.0001024

Explanation:

Answer 2

It is 8/3125

8

3125

Explanation:

It is the second option