Answer:
a) About 12%
Step-by-step explanation:
We need to find the interest rate required to achieve her goal, so we will need to use the interest-compound formula:

Where:
PV= Present Value
i= interest rate
FV= Future Value
n= number of periods
replacing the data provided:

solving for i:
first, divide both sides by 50.000 to simplify the equation:

Take
roots of both sides:
±![\sqrt[10]{3}](https://tex.z-dn.net/?f=%5Csqrt%5B10%5D%7B3%7D)
solve for i:
±![\sqrt[10]{3} -1](https://tex.z-dn.net/?f=%5Csqrt%5B10%5D%7B3%7D%20-1)
We get two answers, but we look for a coherent value. So we take the positive one:
≈12
5 hours + 4 hours = 9 hours
30 minutes + 45 minutes =75 minutes
60 minutes in an hour, so 75 minutes =1 hour and 15 minutes, or 1.25 hours
9 hours + 1.25 hours =10.25 hours or 10 hours and 15 minutes.
Answer:
140y
Step-by-step explanation:
35 times a number times -4 is 35×y×(-4) which is -140y
Here we are given the specific equation of:
amount of eroded soil = 0.4 + 1.3 x
where x is the flow rate
A linear equation has a general formula in the form of:
y = m x + b
where m is the slope and b is the y intercept of the equation
If we compare this with our specific equation, we can see that the slope and y intercept are both positive with values:
m = 0.4
b = 1.3
Therefore this only means that as the flow rate increases, the amount of eroded soil also increases.
Hence the correlation must be positive but we cannot solve for the exact value since we need the data for x and y.
Answer:
positive, but we cannot say what the exact value is