Calculate the amount of simple interest on a loan of $90,000. Interest rate is 8.25% p.a. for a period of 30 months

Mr. Gerald took a bank loan at 12% p.a. flat rate interest. In 3 years, he paid a total of $5,400 interest. Find the principal amount borrowed by Mr. Gerald.

In how many years will $150 earn the same interest at 8%p.a flat rate as $800 earns in 3 years at 4.5%p.a?

Jim invests $20,000 for 4 years and receives $3,200 in interest. Betty invests $20,000 for 3 years and receives $2,700 in interest. What are their flat rates of interest?

Kate borrowed $7000 to go on an overseas holiday, at 9% p.a. flat rate interest for 3 years. Calculate

i) The total interest

ii) The total amount that Kate must repay

After 4 years. the interest on a loan of $5000 amounts to $1600. 

Calculate the annual simple interest rate. 

How many months will it take for $2000 to earn $120, if the interest rate is 4% p.a. 

What amount must be invested to earn $576 at 6% p.a. for 4 years. 

Tony invested $3600 at a bank and earned $112.50 over a period of 15 months. What was the interest rate?