The monthly salary of a person was Rs 320 for each of the first 3 year...
Given:
- Monthly salary for the first 3 years = Rs 320
- Annual increment of Rs 40 per month for the next 12 years
- Average monthly salary during service period = Rs 694
To find:
- Period of service
Approach:
1. Let's assume the period of service is 'x' years.
2. The salary for the first 3 years is Rs 320 per month. So, the total salary for the first 3 years = Rs 320 * 12 * 3 = Rs 11,520.
3. From the 4th year onward, the salary increases by Rs 40 per month. So, the total salary for the next 12 years = Rs 40 * 12 * (x - 3).
4. The total salary for the entire service period can be calculated as:
Total salary = Rs 11,520 + Rs 40 * 12 * (x - 3)
5. The average monthly salary during the service period is given as Rs 694. So, the total salary for the entire service period can also be calculated as:
Total salary = Rs 694 * 12 * x
6. Setting the two equations equal to each other, we get:
Rs 11,520 + Rs 40 * 12 * (x - 3) = Rs 694 * 12 * x
7. Simplifying the equation, we get:
Rs 11,520 + Rs 480 * (x - 3) = Rs 8,328x
Rs 11,520 + Rs 480x - Rs 1,440 = Rs 8,328x
Rs 480x - Rs 8,328x = Rs 1,440 - Rs 11,520
Rs 7,848x = Rs 10,080
x = Rs 10,080 / Rs 7,848
x ≈ 1.283 years
Answer:
The period of service is approximately 1.283 years.