An actor invested some money at 7% and 27,000 more than 4 times the amount at 12%. The total annual interest earned from the investment was $57,140. How much did he invest at each amount?

its not b

step-by-step explanation:

i think the answer would be c

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

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