10(h)+5(h)+7, because 10 and 15 are charged per a hour, so they have a h(house). 7 dollars is a fee that you only pay once. I hope this helps :)
Answer:
<em>The Estimate for the population in 2008 is 33 million </em>
Step-by-step explanation:
<u>Exponential Function</u>
Some real-life situations can be modeled by using the exponential function which takes the form
Where A and k are constants, and t is the independent variable.
We are given two data. A country's population in 1992 was 28 million and in 1999 it was 30 million.
Let's express P as the population in million and t the time in years elapsed since 1992.
The information can be written as two points: (0,28), (7,30). Please recall that the second data comes from the year 1999, seven years after the zero reference.
We only have to replace both points in the general form:
We know A=28 million
Also
Taking logarithms
Solving for k
The model is complete now:
For the year 2008, t=2008-1992=16 years
The Estimate for the population in 2008 is 33 million
Answer:
The total surface area of the pipe is 4123.31 cm²
Step-by-step explanation:
Total surface area (TSA) of a pipe is calculated as;
Outer area of the pipe + Inner area of the pipe + cross section of the two ends
TSA = 2πRL + 2πrL + 2π(R² - r²)
TSA = 2π(RL + rL + R² - r²)
where;
R is the outer radius
r is the inner radius
L is length of the pipe
Determine the length of the pipe
Outer surface area of the pipe is calculated as;
outer surface of the pipe = 2πRL
2514.2 = 2πRL
2514.2 = (2π x 5) L
2514.2 = 31.42 L
L = 2514.2 / 31.42
L = 80.02 cm
Finally, determine the total surface area of the pipe
TSA = 2π(RL + rL + R² - r²)
TSA = 2π(5x80.02 + 3x80.02 + 5² - 3²)
TSA = 2π(400.1 + 240.06 + 16)
TSA = 2π(656.16)
TSA = 4123.31 cm²
Therefore, the total surface area of the pipe is 4123.31 cm²
Answer:
$81.92
Step-by-step explanation:
Week 1:
250 * 20% = 50
250 - 50 = 200
Week 2:
200 * 20% = 40
200 - 40 = 160
Week 3:
160 * 20% = 32
160 - 32 = 128
Week 4:
128 * 20% = 25.6
128 - 25.6 = 102.4
Week 5:
102.4 * 20% = 20.48
102.4 - 20.48 = 81.92
90
Plug in 7 for x and solve.