The simple interest formula is given by:

$I = P \times R \times T$

Where:

• $I$ = Simple interest
• $P$ = Principal (amount invested or borrowed)
• $R$ = Annual interest rate (expressed as a decimal)
• $T$ = Time (in years)

To find the value of any variable in the formula, you'll need values for the other three variables. Here's how to solve for each variable:

1. To find the Interest $I$:

$I = P \times R \times T$ Example: If $P = 1000$ dollars, $R = 0.05$, and $T = 2$ years: $I = 1000 \times 0.05 \times 2 = 100$

2. To find the Principal $P$:

$P = \frac{I}{R \times T}$ Example: If $I = 100$ dollars, $R = 0.05$, and $T = 2$ years: $P = \frac{100}{0.05 \times 2} = 1000$

3. To find the Rate $R$:

$R = \frac{I}{P \times T}$ Example: If $I = 100$ dollars, $P = 1000$ dollars, and $T = 2$ years: $R = \frac{100}{1000 \times 2} = 0.05$

4. To find the Time $T$:

$T = \frac{I}{P \times R}$ Example: If $I = 100$ dollars, $P = 1000$ dollars, and $R = 0.05$: $T = \frac{100}{1000 \times 0.05} = 2 \text{ years}$

Let me know which specific variable you'd like to solve for or if you have particular values in mind.

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Related Questions:

1. What is the simple interest if the principal is $2000, the rate is 3%, and the time is 5 years?
2. How much should be invested at an annual interest rate of 4% to earn $800 in 3 years?
3. If the interest is $150 on a principal of $500 at a 5% annual rate, how many years did it take?
4. What is the annual interest rate if $120 interest is earned on a $600 principal in 4 years?
5. How does the time period affect the amount of interest earned?

Tip: Always ensure that the interest rate $R$ is expressed as a decimal when using the formula (e.g., 5% as 0.05).