Question

Sofia takes 10mg of a medicine whose concentration in blood decreases by a factor of one half every day. Let t be the number of days since Sofia took the medication. The amount of medication in her system after t days is S = 10(½)t. Four days later, Lexi takes 10mg of the same medicine. How much medication, L, is in Lexi’s system on day t?

Answer 1

The correct answer is C.

L = 10 (1/2)^t-4

-nyfb

Answer 2

Answer: Medication in Lexi's system on day t becomes,

`L=10.625((1)/(2))^(t-4)`

Explanation:

Since we have given that

Initial amount Sofia takes of a medicine = 10 mg

Concentration in blood decreases by a factor of one half every day.

So, it becomes,

`S=10((1)/(2))^t\\\\here,\text{ t denotes number of days}`

According to question, four days later, it becomes,

`S=10((1)/(2))^4\\\\S=(10)/(16)\\\\S=0.625\ mg`

We have given that Lexi takes 10 mg of the same medicine.

So, it becomes,

`10+0.625\\\\10.625\ mg`

Hence, Medication in Lexi's system on day t becomes,

`L=10.625((1)/(2))^(t-4)`