Jawahar Navodaya Vidyalaya Selection Test (JNVST)
Your gateway to quality education at Jawahar Navodaya Vidyalaya
Approximation: - making approximation to verify answer during the exam
🚀 Approximation is a useful mathematical technique that helps us quickly estimate the value of a number or the result of a calculation. This is especially helpful during exams when you want to verify your answers without going through lengthy calculations. In the context of the JNVST, approximation can be used to check if your answer is reasonable and close to the expected result. It involves rounding numbers to the nearest ten, hundred, or thousand, depending on the situation, and then performing the calculation with these rounded numbers.
Examples💡
Example 1: Suppose you are buying 3 notebooks, each costing ₹47. Instead of multiplying 47 by 3, you can approximate 47 to 50. So, 50 x 3 = 150. The actual cost is 47 x 3 = 141, which is close to 150, verifying your calculation.
Example 2: If a train travels 123 km in 2 hours, you can approximate 123 to 120. So, 120 km in 2 hours means 60 km per hour. The actual speed is 123/2 = 61.5 km/h, which is close to 60 km/h.
Example 3: You have ₹198 and you want to buy pens costing ₹22 each. Approximate 198 to 200 and 22 to 20. So, 200 ÷ 20 = 10 pens. The actual number of pens you can buy is 198 ÷ 22 ≈ 9 pens, which is close to 10.
Common Mistakes to Avoid⚠️
- Rounding numbers incorrectly, such as rounding 47 to 40 instead of 50.
- Using approximation for exact calculations, which can lead to errors if precision is needed.
- Forgetting to adjust the final answer after using approximation, especially in subtraction or division.