The defect rate for your product has historically been about 1.00%. For a sample size of 400, the upper and lower 3-sigma control chart limits are: UCLp =

Lower limit = -0.05 and Upper limit = 0.025

Step-by-step explanation:

3-sigma , p chart control limits:

Lower limit =

Upper limit = , where n= sample size .

Given: p= 0.01 , n= 400

Lower limit =

Upper limit=

hence, Lower limit = -0.05 and Upper limit = 0.025

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

source:  

4n=2m

ratio of m to n: 2/4 = 1/2

answer

a. 1/2