In Simple Interest when the Time is given in Months and Days

In simple interest when the time is given in months and days we always need to convert into years.

Notes:

(i) When “T’ i.e., the time is given in months then it should be divided by 12 to convert into years.

(ii) When “T’ i.e., the time is given in days then it should be divided by 365 to convert into years.

For example:

1. Tim invested $ 1500 for at the rate of 6% p.a. for 7 years and 3 months. Find the amount he got back.

Solution:

Principal (P) = $ 2000,

Rate (R) = 6% p.a.

Time (T) = 7 years and 3 months.

[We know, when “T’ i.e., the time is given in months then it should be divided by 12 to convert into years].

= 7 3/12 years.

= 7 ¼ years.

= (7 × 4 + 1)/4 years.

= 29/4 years.

Simple Interest (SI) = (P × R × T)/100

Simple Interest (SI) = (2000 × 6 × 29)/(100 × 4)

= 348000/400

= 870

Therefore, Amount = Principal + Simple Interest

= 2000 + 870

Therefore, Amount Tim got back = $ 2870

2. Kyle borrowed $ 3400 at the rate of 8% p.a. for 225 days. Find the interest and amount she paid.

Solution:

Principal = $ 3400,

Rate = 8% p.a.

Time = 225 days.

[We know, when “T’ i.e., the time is given in days then it should be divided by 365 to convert into years].

= 225/365 years.

Simple Interest = (P × R × T)/100

= (3400 × 8 × 225)/(100 × 365)

= 6120000/36500

= $ 167.67

Amount = Principal + Simple Interest

= 3400 + 167.67

= $ 3567.67

Therefore, Amount paid by Kyle is $ 3567.67.

And the Interest paid by Kyle is $ 167.67.