the monthly payment that amortizes a loan of A dollars in t yr when the interest rate is r per year, compounded monthly, is given by

P=f(A,r,t) = Ar/ 12[1-(1+ r/12)^-12t ]
Find the monthly payment for a home mortgage of 300,000 that will be amortized over 30 yr with an interest rate of 6%/year? And interest rate of 8%/year?

To find the monthly payment for a home mortgage of $300,000 that will be amortized over 30 years with an interest rate of 6% per year, we can substitute the given values into the formula for monthly payment:

P = f(A, r, t) = (Ar/12) [1 - (1 + r/12)^(-12t)]

A = $300,000
r = 6% = 0.06 (expressed as a decimal)
t = 30 years

Now we substitute these values into the formula and solve for P:

P = ($300,000 * 0.06/12) [1 - (1 + 0.06/12)^(-12 * 30)]

Simplifying further:

P = $1,500 * [1 - (1 + 0.06/12)^(-360)]

Calculating the exponential part first:

(1 + 0.06/12)^(-360) ≈ 0.55143

Now substitute back into the equation:

P = $1,500 * [1 - 0.55143]

Simplifying:

P = $1,500 * 0.44857

P ≈ $672.86

Therefore, the monthly payment for a home mortgage of $300,000 that will be amortized over 30 years with an interest rate of 6% per year is approximately $672.86.

To calculate the monthly payment with an interest rate of 8% per year, you can follow the same steps, but substitute r = 0.08:

P = f($300,000, 0.08, 30)

P = ($300,000 * 0.08/12) [1 - (1 + 0.08/12)^(-12 * 30)]

Calculate the exponential part:

(1 + 0.08/12)^(-360) ≈ 0.39784

Now substitute back into the equation:

P = $2,000 * [1 - 0.39784]

Simplifying:

P = $2,000 * 0.60216

P ≈ $1,204.32

Therefore, the monthly payment for a home mortgage of $300,000 that will be amortized over 30 years with an interest rate of 8% per year is approximately $1,204.32.

To find the monthly payment for a home mortgage of $300,000 that will be amortized over 30 years with an interest rate of 6% per year (compounded monthly), we can use the given formula:

P = f(A, r, t) = (A * r/12) / [1 - (1 + r/12)^(-12t)]

Replacing the variables with the given values:
A = $300,000
r = 6% = 0.06
t = 30

Let's calculate the monthly payment:

For an interest rate of 6% per year:
P = (300,000 * 0.06/12) / [1 - (1 + 0.06/12)^(-12*30)]

To calculate this, let's break down the formula further into steps:

Step 1: Calculate the monthly interest rate:
Divide the annual interest rate by 12.
r/12 = 0.06/12 = 0.005

Step 2: Calculate the number of months:
Multiply the number of years by 12.
t = 30 * 12 = 360

Step 3: Calculate the value inside the square brackets:
(1 + r/12)^(-12t) = (1 + 0.005)^(-12 * 360)

Step 4: Calculate the monthly payment:
P = (300,000 * 0.005) / [1 - (1 + 0.005)^(-12 * 360)]

Calculating each step and simplifying the expression, we get:

P = $1,798.65

Therefore, the monthly payment for a home mortgage of $300,000, amortized over 30 years with an interest rate of 6% per year, is $1,798.65.

Now, let's calculate the monthly payment for an interest rate of 8% per year using the same formula and steps:

Replacing the variables with the new values:
A = $300,000
r = 8% = 0.08
t = 30

P = (300,000 * 0.08/12) / [1 - (1 + 0.08/12)^(-12 * 30)]

Calculating each step and simplifying the expression, we get:

P = $2,202.29

Therefore, the monthly payment for a home mortgage of $300,000, amortized over 30 years with an interest rate of 8% per year, is $2,202.29.