Basic Concept of Estimation and Approximation of Numbers

Estimation is the process of determining an approximate value by rounding numbers to the nearest ten, hundred, thousand, or other place value to simplify calculations and judgements about size, cost, quantity, or other measurements.

1. When a school plans an event (like Sports Day), they need to know roughly how much money they will spend.

1. Expenditure on invitation cards              = ₹  1,530
2. Expenditure on hiring the furniture        = ₹   7,250
3. Expenditure on the dress of participants = ₹ 11,638
4. Expenses on transportation                     = ₹   4,547
5. Expenditure on refreshments                  = ₹   2,590
6. Miscellaneous expenses                          = ₹   6,240
   Total estimate (approximate expenses)  = ₹ 33,795

2. In a cricket match between India and Pakistan, 63,000 spectators watched the match sitting in the stadium and 53 million television viewers worldwide. Explain the  statement.
Does the statement above indicate that exactly 63,000 spectators were in the stadium, or does it say that exactly 53 million viewers watched the match on television? 

Explanation:
Saying 63,000 spectators at a match doesn’t mean exactly 63,000 people—it might be 62,500 or 64,000. It’s just close.

Saying 53 million viewers on TV means around 53 million—maybe 52.6 or 54 million.

Saying half an acre of land, about 800 m away, or around 200 guests at a wedding are all approximations.

3. Shopping Estimate: If invitation cards cost ₹1,530, furniture ₹7,250, and dresses ₹11,638, round and add for a quick estimate:

• Cards: ₹1,500
• Furniture: ₹7,000
• Dresses: ₹12,000
• Estimated total: ₹1,500 + ₹7,000 + ₹12,000 = ₹20,500