Answer:

To calculate the amount of money Mylene would have in 9 years and 6 months, given that the interest rate increased to 15% converted quarterly 4 years later, we can use the formula for compound interest:

A = P(1 + r/n)^(nt)

Where:

A = accumulated amount

P = principal (initial investment)

r = interest rate

n = number of times the interest is compounded per year

t = number of years

For the first 4 years:

r = 0.14 (14% interest rate)

n = 4 (quarterly compounded)

t = 4

A = P(1 + r/n)^(nt)

A = 1,000,000 (1 + 0.14/4)^(4*4)

A = 1,581,209.80

For the next 5 years and 6 months:

r = 0.15 (15% interest rate)

n = 4 (quarterly compounded)

t = 5.5 (5 years and 6 months expressed in decimal)

A = P(1 + r/n)^(nt)

A = 1,581,209.80 (1 + 0.15/4)^(4*5.5)

A = 2,554,460.91

So the accumulated amount after 9 years and 6 months is P2,554,460.91

It is worth noting that this calculation is an approximation and doesn't take into account other variables such as taxes, fees and other charges.

Step-by-step explanation:

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