Step 1
Given;
Required; To find the difference in interest between the two periods.
Step 2
State the formula for simple interest
Step 3
Find the interest when the rate is 8%
Therefore the interest is given as;
Step 4
Find the interest in 1980 with a 20% rate
The interest is given as;
Step 5
Find the difference in interest between the two rates.
Hence, the difference in interest between the two rates = $11095.89