Answer:
For this case we need to check the conditions in order to use the normal approximation:
1) 
2) 
Since both conditions are satisfied and the independence condition is assumed we can use the normal approximation given by:

The mean would be given by:

And the deviation is given by:

Step-by-step explanation:
For this case we know the following info:
n =60 represent the sample size
represent the estimated proportion of people that will buy a packet of crackers after tasting
For this case we need to check the conditions in order to use the normal approximation:
1) 
2) 
Since both conditions are satisfied and the independence condition is assumed we can use the normal approximation given by:

The mean would be given by:

And the deviation is given by:

Answer:
4 and 15
Step-by-step explanation:
Let the two numbers be a and b.
The sum of the two is 19. Therefore:

One number (let's use a) is 7 <em>more</em> than twice the other. Thus:

Solve for the system of equations. Substitute the second equation into the first:

Subtract 7 from both sides:

Combine like terms:

Divide by 3:

So, b is 4.
And since they add up to 19, this means that a is:

So our numbers are 4 and 15
And we are done :)
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:um....
Step-by-step explanation: