multiply the top equation by 3, multiply the bottom equation by 4, then subtract the bottom equation from the top equation
multiply the top equation by 3, multiply the bottom equation by -2, then add the equations
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%.
You would find the answer by solving shxndbsinsnsndidndnid dbdoamsidbdhdbd
Answer:
$11.25
Step-by-step explanation:
Multiply the number of hours she works by how much she gets paid per hour.
800
Multiply 50 times 7 (50 being the amount charged for her kid and 7 being the days of the week)
350
Subtract the 350 from the 800
450
Divide the 450 by the number of hours worked per week
450/40
Answer: 11.25
So Sally actually makes 11.25 per hour.