Answer:
∴35.97 mg caffeine would be left in the system after 5 hours.
Step-by-step explanation:
Given that,
A cup of coffee has approximately 310 mg of caffeine.
Caffeine decrease at a rate 35% per hour.
Exponential Function:
y(t)= Amount caffeine after t hours
= Initial amount of caffeine
r= rate of decrease
t = Time in hour.
Here y(t)=?, = 310 mg, r=35%=0.35, t= 5 hours
=35.97 mg
∴35.97 mg caffeine would be left in the system after 5 hours.
Answer:
- 26 ounces of 55% solution
- 104 ounces of 80% solution
Step-by-step explanation:
Let x represent the quantity of 80% solution. Then 130-x is the amount of 55% solution. The total amount of salt in the mix is ...
0.80x +0.55(130 -x) = 0.75·130
0.25x = 0.20·130 . . . . . . . subtract 0.55(130)
x = 0.20/0.25(130) = 104
130-x = 26
She should use 26 ounces of 55% solution and 104 ounces of 80% solution.
Answer:
Step-by-step explanation:
6x+9=63
6x=63-9
6x=54
x=54/6
x=9
I encourage you to figure out the justification yourself.
