Finding Time when Principal and Rate are given

In this section you will learn finding time when principal and rate are given in easy way. The time period may be in years, days or in months. For everyone we have different formulas.

When time in years

      S.I x 100
Time = T = -------------
P x R

When time in days

      S.I x 100 x 365
Time = T = ----------------
P x R

When time in months

      S.I x 100 x 12
Time = T = ----------------
P x R

Examples :

1) Principal = P = $3500, S.I = $700 and rate = R = 5%. Find the time period in years.

Solution :
                  S.I x 100
Time = T = -------------
                    P x R

                  700 x 100
Time = T = -------------
                    3500 x 5

                  70,000
Time = T = -------------
                    17,500

Time = 4 years.
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2) Principal = P = $4800, S.I = $900 and rate = R = 7.5%. Find the time period in months.

Solution :
                  S.I x 100
Time = T = -------------
                    P x R

                  900 x 100 x 12
Time = T = -------------
                    4800 x 7.5

                  1,080,000
Time = T = -------------
                    36000

Time = 30 months.
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3) Principal = P = $7300, S.I = $500 and rate = R = 4%. Find the time period in days.

Solution :

S.I x 100 Time = T = ------------- P x R 500 x 100 x 365 Time = T = ------------- 7300 x 5 18250000 Time = T = ------------- 36500 Time = 500 days.

Practice
Complete the following table:

Principal (P)	Rate (R)	Time(T)	Simple interest (SI)
$8000	6 %	-	$450
$5664	13 ¾	- (in month)	$584.10
$3125	15%	- (in days)	$93.75
$500	7%	- (in years)	105
$250	8%	- (in years)	$80

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Simple Interest (S.I)

• Finding rate when Principal and time are given
• Finding time when Principal and rate are given
• Solved examples on Simple Interest

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