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# Simple interest calculator

Simple interest is calculated only on the initial amount (principal) that you invested.

Example: Suppose you give \$100 to a bank which pays you 5% simple interest at the end of every year. After one year you will have \$105, and after two years you will have \$110. This means that you will not earn an interest on your interest. Your interest payments will be$5 per year no matter how many years the initial sum of money stays in a bank account.

This calculator can be used to solve various types of simple interest problems. The calculator will print easy to understand step-by-step explanation. Click here to see a list of example problems that can be solved by using this calculator.

Problem

You deposit $12000 into a bank account paying 1.5% simple interest per month. You left the money in for 210 days. Find the interest earned and the amount at the end of those 210 days? Result The interest is$1242.734 and the amount is $13242.734. Explanation STEP 1: Convert interest rate of 1.5% per month into rate per year. $$\text{rate per year = rate per month} \cdot 12 = 1.5 \% \cdot 12 = 18 \%$$ STEP 2: Convert 210 days into years. $$\text{ 210 days } = \frac{ 210 }{365} \text{ years} = 0.57534 \text{ years}$$ STEP 3: Find an interest by using the formula$ I = P \cdot i \cdot t $, where I is interest, P is total principal, i is rate of interest per year, and t is total time in years. In this examplee P =$12000, i = 18% and t = 0.57534 years, so

\begin{aligned} I &= P \cdot i \cdot t \\ I &= 12000 \cdot 0.18 \cdot 0.57534 \\ I &= 1242.734 \end{aligned}

STEP 4: Find an amount by using the formula $A = P + I$.

Since P = $12000 and I =$1242.734 we have

\begin{aligned} A &= P + I \\ A &= 12000 + 1242.734 \\ A &= 13242.734 \end{aligned}

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Script name : simple-interest-calculator

Imputed values: 0 , 12000 , 1.5 , 3 , 210 , 3

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Simple Interest Calculator
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Simple Interest Calculator
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## Simple Interest Problems

This is a list of the example problems which can be solved by using this calculator.

### Problems with unknown interest and amount

Example 1: You deposit \$1000 into a bank account paying 7% simple interest per year. You left the money in for 3 years. Find the interest earned and the amount at the end of those 3 years?  Set up the form View the solution Example 2: You deposit \$12000 into a bank account paying 1.5% simple interest per month. You left the money in for 210 days. Find the interest earned and the amount.

 Set up the form View the solution

### Problems with unknown principal

Example 3: You deposit some money into a bank account paying 4% simple interest per year. You received $72 in interest after 3 years. How much the deposit (principal) was?  Set up the form View the solution Example 4: You deposit some money into a bank account paying 2% simple interest per 6 months. You received$15 in interest after 9 month. How much the principal was?

 Set up the form View the solution

### Example with unknown interest rate

Example 5: You deposit $1000 into a bank account and received$50 simple interest after 3 months. What had been the interest rate?

 Set up the form View the solution

### Example with unknown time period

Example 6: You deposit $350 into a bank account paying 1.2% simple interest per month. If you receiver$9 as interest, find the time for which the money stayed at the bank.

 Set up the form View the solution

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