loala has a balance- of $50 in her bank account. she deposits into the account each week for 3 weeks. The fourth week loala withdrawal $15. What was the balance in loalas bananas account after the withdrawal in the fourth week?

answer: i think it is (1,-2)

probably the last option

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

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