DSC1630
Assignment 1
Semester 1
Due 13 March 2026
,Question 1
Problem
Hassim deposits R900 into a savings account paying 6.5% per year compounded
quarterly. After 3.5 years he withdraws R1 000 and leaves the rest invested. Find the
value remaining in the first account two years later.
Calculate value after 3.5 years
Quarterly rate = 0.065 ÷ 4 = 0.01625
Number of quarters = 3.5 × 4 = 14
𝐴1 = 900(1.01625)14 ≈ 1127.70
Subtract withdrawal
1127.70 − 1000 = 127.70
Grow remaining balance for 2 more years
Number of quarters = 2 × 4 = 8
𝐴2 = 127.70(1.01625)8 ≈ 145.23
Final Answer:
𝑅145
, Question 2
After depositing R1 000 at 11% simple interest, the amount grows to R1 605. Find the
time invested.
Simple interest formula:
0.605
𝑆 = 𝑃 (1 + 𝑟𝑡) 1605 = 1000 (1 + 0.11𝑡) 𝑡 = 0.11
= 5.50 years
Final Answer:
5.50 years
Assignment 1
Semester 1
Due 13 March 2026
,Question 1
Problem
Hassim deposits R900 into a savings account paying 6.5% per year compounded
quarterly. After 3.5 years he withdraws R1 000 and leaves the rest invested. Find the
value remaining in the first account two years later.
Calculate value after 3.5 years
Quarterly rate = 0.065 ÷ 4 = 0.01625
Number of quarters = 3.5 × 4 = 14
𝐴1 = 900(1.01625)14 ≈ 1127.70
Subtract withdrawal
1127.70 − 1000 = 127.70
Grow remaining balance for 2 more years
Number of quarters = 2 × 4 = 8
𝐴2 = 127.70(1.01625)8 ≈ 145.23
Final Answer:
𝑅145
, Question 2
After depositing R1 000 at 11% simple interest, the amount grows to R1 605. Find the
time invested.
Simple interest formula:
0.605
𝑆 = 𝑃 (1 + 𝑟𝑡) 1605 = 1000 (1 + 0.11𝑡) 𝑡 = 0.11
= 5.50 years
Final Answer:
5.50 years
