To solve this problem, we start by using the simple interest formula, which is: Simple Interest (SI) = Principal (P) × Rate (R) × Time (T). Given that \(800\) becomes \(956\) in three years, we can deduce the interest earn by calculating \(956 - 800 = 156\).
Step 1: Calculate the original rate of interest.
The principal (P) is \(800\), the interest (SI) is \(156\), and the time (T) is \(3\) years. Using the formula, we have:
\(156 = 800 \times R \times 3\).
Solving for \(R\), we get:
\(R = \frac{156}{800 \times 3} = \frac{1}{15}\) or about \(6.67\%\).
Step 2: Increase the interest rate by 3%.
The new rate \(R_{new} = 6.67\% + 3\% = 9.67\%\).
Step 3: Calculate the new amount after 3 years with the increased rate.
The new interest \(SI_{new}\) will be:
\(SI_{new} = 800 \times \frac{9.67}{100} \times 3\).
Thus, \(SI_{new} = 800 \times 0.0967 \times 3 = 232.08\).
Step 4: Calculate the new total amount.
Adding the new interest to the principal gives:
\(Total = 800 + 232.08 = 1032.08\).
However, based on the closest provided options, rounding \(1032.08\) to the nearest sensible option, we choose 1028 as the closest match.