Here is a list of ingredients for making 16 flapjacks. Ingredients for 16 flapjacks
120 g butter
140 g brown sugar
250 g oats
2 tablespoons syrup
jenny wants to make 24 flapjacks.
work out how much of each of the ingredients she needs.

butter
brown sugar
oats
syrup tablespoons ​

2 1/2 feet

step-by-step explanation:

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: