Ali saved RM15,000 on 10 May 2014 in an account that offers r% simple interest per year. If the simple interest earned on 25 October 2014 is RM 120, find the value of r using exact time.
To find the value of r, we need to know the time period between 10 May 2014 and 25 October 2014.
First, let's find the number of days between the two dates:
10 May 2014 to 25 October 2014:
- May: 31 days
- June: 30 days
- July: 31 days
- August: 31 days
- September: 30 days
- October: 25 days
Total days = 31 + 30 + 31 + 31 + 30 + 25 = 178 days
Next, let's find the yearly interest rate, r:
Simple interest = Principal x Rate x Time
RM120 = RM15,000 x r x (178/365)
Simplifying the equation:
RM120 = RM15,000 x r x (0.4877)
Divide both sides of the equation by RM15,000 x 0.4877:
r = RM120 / (RM15,000 x 0.4877)
r ≈ 0.0164 or 1.64%
Thus, the value of r is approximately 1.64%.