One and 3/20 can't be simplified
Simplies form of 3/8 is 1/4
Answer:
The function that represents the mass of the sample after t days is
.
The percentage rate of change per hour is of -2.46%.
Step-by-step explanation:
Exponential amount of decay:
The exponential amount of decay for an amount of a substance after t days is given by:

In which A(0) is the initial amount, and r is the decay rate, as a decimal.
Element X is a radioactive isotope such that its mass decreases by 59% every day. The experiments starts out with 390 grams of Element X.
This means, respectively, that 
So



The function that represents the mass of the sample after t days is
.
Hourly rate of change:
Decreases by 59% every day, which means that for 24 hours, the rate of change is of -59%. So
-59%/24 = -2.46%
The percentage rate of change per hour is of -2.46%.
Answer: B.The cost of rental fee only
Step-by-step explanation:
The $35 is the cost of the rental fee only. The person would then have to pay a further $15 for every hour they use the boat.
Essentially, the $35 is the fixed cost associated with the rental and the $15 is the variable cost to do so. If this were in a linear equation format it would take the form: y = 15x + 35.