A man has a simple discount note for ​$6 comma 500​, at an ordinary bank discount rate of 8.61 % comma for 50 days. What is the effective interest​ rate? Round to the nearest tenth of a percent

A man has a simple discount note for ​$6,500​ at an ordinary bank discount rate of 8.61 %, for 50 days. What is the effective interest​ rate? Round to the nearest tenth of a percent

To find the effective interest rate, we need to first calculate the discount amount and then use it to find the effective interest rate.

Step 1: Calculate the Discount Amount
The discount amount on a simple discount note can be found using the formula:
Discount Amount = Principal × Interest Rate × Time

Given:
Principal (P) = $6,500
Interest Rate (R) = 8.61% (expressed as a decimal by dividing by 100) = 0.0861
Time (T) = 50 days

Discount Amount = $6,500 × 0.0861 × 50

Step 2: Calculate the Effective Interest Rate
The effective interest rate can be found using the formula:
Effective Interest Rate = (Discount Amount / Principal) × (365 / Time)

Effective Interest Rate = (Discount Amount / Principal) × (365 / Time)
Note: 365 is used since the time is given in days.

Effective Interest Rate = (Discount Amount / $6,500) × (365 / 50)

Now, let's calculate the Discount Amount:
Discount Amount = $6,500 × 0.0861 × 50
= $2,791.25

Substituting the values:
Effective Interest Rate = ($2,791.25 / $6,500) × (365 / 50)

Calculating:
Effective Interest Rate ≈ 0.4291 × 7.3
Effective Interest Rate ≈ 3.1287

Rounding to the nearest tenth of a percent:
Effective Interest Rate ≈ 3.1%

Therefore, the effective interest rate is approximately 3.1%.