The exponential functions change is represented by decay and the percentage rate of decrease is 1.00619%.
Step-by-step explanation:
Step 1:
To determine if the function represents growth or decay, we substitute values to x.
If the values increase with an increase of x, it represents growth.
If the values decrease with an increase of x, it represents decay.
Step 2:
If 
If 
So as x increases the value of y decreases, so it represents decay.
Step 3:
The percentage rate of change is determined by dividing the difference of two consecutive values by the first value.
The percentage rate of change 
Substituting the values, we get
The percentage rate of change 
.
As the values of y decrease with an increase in x, it is the percent decrease per unit.
Answer:
Step-by-step explanation:
Let x be the random variable representing the times a fire department takes to arrive at the scene of an emergency. Since the population mean and population standard deviation are known, we would apply the formula,
z = (x - µ)/σ
Where
x = sample mean
µ = population mean
σ = standard deviation
From the information given,
µ = 6 minutes
σ = 1 minute
the probability that fire department arrives at the scene in case of an emergency between 4 minutes and 8 minutes is expressed as
P(4 ≤ x ≤ 8)
For x = 4,
z = (4 - 6)/1 = - 2
Looking at the normal distribution table, the probability corresponding to the z score is 0.023
For x = 8
z = (8 - 6)/1 = 2
Looking at the normal distribution table, the probability corresponding to the z score is 0.98
Therefore,
P(4 ≤ x ≤ 8) = 0.98 - 0.23 = 0.75
The percent of emergencies that the fire department arrive at the scene in between 4 minutes and 8 minutes is
0.75 × 100 = 75%
Answer:
The answer is 7(x + 25)
Step-by-step explanation:
The question states 25 push-ups plus x amount of push-ups per day. To find how many push-ups per week, we multiply how many push-ups per day by 7 (a week).
