Question

a.Dr. Vaccarro invested his money at 12.5% for 175 days and earned interest of $760. How much money did Dr. Vaccarro invest?

b.In June, Becky opened a $20,000 bank CD paying 1% interest, but she had to withdraw the money in a few days to cover one child's college tuition. The bank charged her $1,000 in penalties for the withdrawal. What percent of the $20,000 was she charged

c.Find how long in days David Wong must invest $23,500 of his company's cash at 8.4% in order to earn $652.50 in interest

d.John Joseph borrowed $10,800 for 1 year at 14%. After 60 days, he paid $2,500 on the note. On the 200th day, he paid an additional $5,000. Use the U.S. Rule and ordinary interest to find the final balance due

Answer 1

Answer (a)

Let amount invested be X

So, (X*12.50%)*(175/365) = $760

X = $12,680

Answer (b)

Penalties percentage = ($1,000/$20,000)*100

= 5%

Answer (c)

The annual interest will be = $23,500*8.4%

= $1,974

Days required to earn interest of $652.50 = (365/1974)*652.50

= 121 days approx

Answer (d)

Calculation of interest payable-

On $2,500 = (2,500*14%)*(60/365) = $57.53

On $5,000 = (5,000*14%)*(200/365) = $383.56

On remaining $3,300 = (3,300*14%)*(365/365) = $462

Final balance due after 1 year will be = $3,300+$462

= $3,762