NPrep
Start practising
NORCET 3 - 2022 (Shift-1)
Quantitative Aptitude and Mathematics
Hard

After 4 years, a principal amount of Rs. 12000 grows into Rs. 14400. Find out the rate of simple interest.

Appeared in: NORCET 3 - 2022 (Shift-1)

Explanation

  • The first step is to calculate the total simple interest earned over the 4-year period by subtracting the principal from the final amount (14,400 - 12,000 = 2,400).
  • The formula for Simple Interest (SI) is SI = (P × R × T) / 100, where P is the principal, R is the rate, and T is the time.
  • Substitute the known values into the formula: 2,400 = (12,000 × R × 4) / 100.
  • Solving the equation for R gives: R = (2,400 × 100) / (12,000 × 4).
  • This simplifies to R = 240,000 / 48,000, which equals 5.
  • Thus, the rate of simple interest is 5% per annum.

Why Other Options Were Wrong

  • Option A: A rate of 3% would yield a simple interest of (12000 × 3 × 4) / 100 = Rs. 1,440, not Rs. 2,400.
  • Option B: A rate of 4% would yield a simple interest of (12000 × 4 × 4) / 100 = Rs. 1,920, not Rs. 2,400.
  • Option D: A rate of 6% would yield a simple interest of (12000 × 6 × 4) / 100 = Rs. 2,880, not Rs. 2,400.

Related Visual

An infographic illustrating the formula for Simple Interest: SI \= P × R × T / 100, with each component Principal, Rate, Time, Interest clearly defined and visually represented.
  • Visual 1: Infographic - An infographic illustrating the formula for Simple Interest: SI = (P × R × T) / 100, with each component (Principal, Rate, Time, Interest) clearly defined and visually represented.
Clinical Relevance
  • Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Calculation of Simple Interest Rate as background academic context rather than a clinical decision trigger.
  • This question assesses basic mathematical and aptitude skills, which are a component of many nursing entrance examinations.
  • While not a direct clinical skill, proficiency in basic calculations is essential for tasks like medication dosage calculation, fluid balance monitoring, and data interpretation in a clinical setting.
  • What if the interest was compounded annually? The calculation would be more complex, using the formula A = P(1 + R/100)^T, and the resulting rate would be different.
How to Approach the Question
  • First, identify all the given values in the problem: Principal (P), Amount (A), and Time (T).
  • Calculate the Simple Interest (SI) by finding the difference between the final Amount and the initial Principal (SI = A - P).
  • Recall the standard formula for Simple Interest: SI = (P × R × T) / 100.
  • Substitute the known values of SI, P, and T into the formula.
  • Rearrange the formula to solve for the unknown variable, which is the Rate (R).
  • Perform the calculation carefully to find the value of R and select the matching option.
Concept Tested & Keywords
  • Concept Tested: Calculation of Simple Interest Rate
  • Stem keywords: principal amount, grows into, rate of simple interest, Rs. 12000, Rs. 14400, 4 years
  • Lead-in keywords: Find out

Question ID

QtHBWy41TpKjH9Bf6JmsK4

Practise the full NORCET 3 - 2022 (Shift-1)

Attempt every question from this paper in a timed mock, then review the full solution for each one.

Attempt this paperAttempt in the NPrep app

More Simple interest Questions

More NORCET 3 - 2022 (Shift-1) Questions