In the previous segments, we learnt how to round off numbers to their nearest 10s, 100s and 1000s. In this segment, we will learn how to use estimation on outcomes of mathematical operations like addition, subtraction and multiplication.
Mathematical operations
Let us look at the conventional way of finding the sum, difference and product of numbers with the help of examples:
| Sum or Addition ( + ) | Difference or Subtraction ( – ) | Product or Multiplication ( x ) |
| 235 + 3570+ 699 | 7350 – 916 | 175 x 23 |
| 235
+ 3570 + 699 ——— 4504 |
7305
– 916 ——— 6389 |
175
x 23 ——— 525 + 3500 4025 |
But there are situations where the exact value of something is not required and the estimated sum and difference is more than enough.
Let us look at a situation where estimation is a better option than calculating the exact value.
Raj has 2000 rupees. He wants to buy a gift for his friend as well as a drawing kit for himself. The cost of each item is given below:
Gift: 1119 Rs.
