Over the last 3 evenings, Donna received a total of 154 phone calls at the call center. The third evening, she received 4 times as many calls as the first evening. The first evening, she received 10 fewer calls than the second evening. How many phone calls did she receive each evening?

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hope this !

use distributive property on all like terms and change your signs if you have a double negative or if you have positive/negative

the awnser is visionary

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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