Responder
- **Part a:** R7.73
- **Part b:** R137,503.69
- **Part c:** 6.19%
- **Part d:** R116,139.71
Solución
Let's break down each part of the problem step by step.
### Part a
We need to calculate the future value of an investment of R5, compounded annually at a rate of \( 9.1\% \) for 5 years.
The formula for compound interest is given by:
\[
A = P(1 + r)^n
\]
where:
- \( A \) = the amount of money accumulated after n years, including interest.
- \( P \) = the principal amount (the initial amount of money).
- \( r \) = the annual interest rate (decimal).
- \( n \) = the number of years the money is invested or borrowed.
**Given:**
- \( P = 5 \)
- \( r = 9.1\% = 0.091 \)
- \( n = 5 \)
Now, we can substitute these values into the formula.
### Part b
We need to calculate the future value of an investment of R100,000 at \( 11.2\% \) compounded annually for 3 years.
Using the same formula:
\[
A = P(1 + r)^n
\]
**Given:**
- \( P = 100000 \)
- \( r = 11.2\% = 0.112 \)
- \( n = 3 \)
### Part c
We need to find the interest rate \( r \) that must be invested to grow R20,000 to R27,000 in 5 years using compound interest.
We can rearrange the compound interest formula to solve for \( r \):
\[
A = P(1 + r)^n \implies 1 + r = \left(\frac{A}{P}\right)^{\frac{1}{n}} \implies r = \left(\frac{A}{P}\right)^{\frac{1}{n}} - 1
\]
**Given:**
- \( A = 27000 \)
- \( P = 20000 \)
- \( n = 5 \)
### Part d
We need to calculate the original amount invested if R150,000 is accumulated in 5 years at an interest rate of \( 5.25\% \) compounded annually.
Using the rearranged formula:
\[
P = \frac{A}{(1 + r)^n}
\]
**Given:**
- \( A = 150000 \)
- \( r = 5.25\% = 0.0525 \)
- \( n = 5 \)
Now, let's perform the calculations for each part.
Calculate the value by following steps:
- step0: Calculate:
\(100000\left(1+0.112\right)^{3}\)
- step1: Add the numbers:
\(100000\times 1.112^{3}\)
- step2: Convert the expressions:
\(100000\left(\frac{139}{125}\right)^{3}\)
- step3: Simplify:
\(100000\times \frac{139^{3}}{125^{3}}\)
- step4: Rewrite the expression:
\(3125\times 32\times \frac{139^{3}}{125^{3}}\)
- step5: Rewrite the expression:
\(5^{5}\times 32\times \frac{139^{3}}{5^{9}}\)
- step6: Reduce the numbers:
\(32\times \frac{139^{3}}{5^{4}}\)
- step7: Multiply:
\(\frac{32\times 139^{3}}{5^{4}}\)
- step8: Simplify:
\(\frac{32\times 139^{3}}{625}\)
Calculate or simplify the expression \( 150000/(1 + 0.0525)^5 \).
Calculate the value by following steps:
- step0: Calculate:
\(\frac{150000}{\left(1+0.0525\right)^{5}}\)
- step1: Add the numbers:
\(\frac{150000}{1.0525^{5}}\)
- step2: Convert the expressions:
\(\frac{150000}{\left(\frac{421}{400}\right)^{5}}\)
- step3: Simplify the expression:
\(\frac{150000}{\frac{421^{5}}{400^{5}}}\)
- step4: Rewrite the expression:
\(\frac{150000\times 400^{5}}{421^{5}}\)
Calculate or simplify the expression \( (27000/20000)^(1/5) - 1 \).
Calculate the value by following steps:
- step0: Calculate:
\(\left(\frac{27000}{20000}\right)^{\frac{1}{5}}-1\)
- step1: Reduce the fraction:
\(\left(\frac{27}{20}\right)^{\frac{1}{5}}-1\)
- step2: Rewrite the expression:
\(\frac{27^{\frac{1}{5}}}{20^{\frac{1}{5}}}-1\)
- step3: Calculate:
\(\frac{27^{\frac{1}{5}}\times 20^{\frac{4}{5}}}{20}-1\)
- step4: Reduce fractions to a common denominator:
\(\frac{27^{\frac{1}{5}}\times 20^{\frac{4}{5}}}{20}-\frac{20}{20}\)
- step5: Transform the expression:
\(\frac{27^{\frac{1}{5}}\times 20^{\frac{4}{5}}-20}{20}\)
- step6: Simplify:
\(\frac{2\sqrt[5]{5000}\times \sqrt[5]{27}-20}{20}\)
- step7: Reduce the fraction:
\(\frac{\sqrt[5]{135000}-10}{10}\)
Calculate or simplify the expression \( 5*(1 + 0.091)^5 \).
Calculate the value by following steps:
- step0: Calculate:
\(5\left(1+0.091\right)^{5}\)
- step1: Add the numbers:
\(5\times 1.091^{5}\)
- step2: Convert the expressions:
\(5\left(\frac{1091}{1000}\right)^{5}\)
- step3: Simplify:
\(5\times \frac{1091^{5}}{1000^{5}}\)
- step4: Rewrite the expression:
\(5\times \frac{1091^{5}}{125^{5}\times 8^{5}}\)
- step5: Rewrite the expression:
\(5\times \frac{1091^{5}}{5^{15}\times 8^{5}}\)
- step6: Reduce the numbers:
\(1\times \frac{1091^{5}}{5^{14}\times 8^{5}}\)
- step7: Multiply the fractions:
\(\frac{1091^{5}}{32768\times 5^{14}}\)
### Part a
The future value of R5 compounded annually at \( 9.1\% \) for 5 years is calculated as follows:
\[
A = 5(1 + 0.091)^5 \approx 7.73
\]
So, the amount after 5 years will be approximately **R7.73**.
### Part b
The future value of R100,000 compounded annually at \( 11.2\% \) for 3 years is:
\[
A = 100000(1 + 0.112)^3 \approx 137503.69
\]
Thus, the amount after 3 years will be approximately **R137,503.69**.
### Part c
To find the interest rate \( r \) that grows R20,000 to R27,000 in 5 years:
\[
r = \left(\frac{27000}{20000}\right)^{\frac{1}{5}} - 1 \approx 0.06186
\]
This means the interest rate must be approximately **6.19%**.
### Part d
To calculate the original amount invested if R150,000 is accumulated in 5 years at an interest rate of \( 5.25\% \):
\[
P = \frac{150000}{(1 + 0.0525)^5} \approx 116139.71
\]
Thus, the original amount invested was approximately **R116,139.71**.
### Summary of Results:
- **Part a:** R7.73
- **Part b:** R137,503.69
- **Part c:** 6.19%
- **Part d:** R116,139.71
Respondido por UpStudy AI y revisado por un tutor profesional
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