Question 1: Write the formula to calculate the amount after 'n' months at a monthly compound interest rate 'r'.

Answer: A = P(1 + r)^n

Question 2: Calculate the amount accumulated if $1,200 is invested at a monthly interest rate of 1.5% for 6 months. Show your working.

Answer: A = 1200*(1+0.015)^6 ≈ 1200*1.093166 ≈ 1311.80

Question 3: If the same $1,200 grows to $1,311.80 in 6 months, what is the monthly interest rate 'r'? Show your working.

Answer: r ≈ ( (1311.80/1200) )^(1/6) - 1 ≈ 1.093166^(1/6) - 1 ≈ 0.015 or 1.5%

Question 4: A sum of $800 is invested at a monthly compound interest rate of 2%. What will be the total after 12 months? Show your calculations.

Answer: A = 800*(1+0.02)^12 ≈ 800*1.2682418 ≈ 1014.59

Question 5: Plot the graph of y = 1.02^x for x from 0 to 12. (Draw on grid)

Answer: Student draws the exponential growth curve for the interest factor over 12 months.

Question 6: Construct a circle of radius 5 units on the grid. Using the same scale, construct a square with a side length of 4 units.

Answer: Student draws the geometric shapes as instructed.

Question 7: A bank offers 2.5% interest compounded monthly. How much money will $400 grow to in 1 year? Show working.

Answer: A = 400*(1+0.025)^12 ≈ 400*1.3498588 ≈ 539.94

Question 8: A friend invests $950 at a monthly interest rate of 1.8%. How long will it take for the investment to grow to $1,100? Show your working.

Answer: n = log(1100/950) / log(1+0.018) ≈ log(1.1579) / log(1.018) ≈ 0.0642 / 0.0178 ≈ 3.61 months

Question 9: Identify and correct the mistake: If interest is compounded monthly at 3%, after 6 months the amount is calculated as A = P*(1+0.03)^6. Is this correct? Why or why not?

Answer: Incorrect; the monthly rate should be 0.03 (3%), so the formula is correct for monthly compounding.

Question 10: Compare the total amount after 12 months for investments at 2% and 3% monthly interest rates, both starting with $1,000. Which yields more and why?

Answer: At 2%: 1000*(1.02)^12 ≈ 1267.2; at 3%: 1000*(1.03)^12 ≈ 1426.9; 3% yields more due to higher monthly growth rate.