Estimating Sum and Difference

The procedure of estimating sum and difference are in the following examples.

Example 1:

Estimate the sum 5290 + 17986 by estimating the numbers to their nearest (i) hundreds (ii) thousands.

Solution:

(i) Estimating the numbers 5290 and 17986 to their nearest hundreds, we get 5300 and 18000 respectively.

We have,

Estimating Sum and Difference





Therefore, estimated sum is 23300.

(ii) Estimating the numbers 5290 and 17986 to their nearest 

hundreds, we get 5000 and 18000 respectively.

We have, 

Estimated Sum is 23000





Therefore, estimated sum is 23000.


Example 2:

Estimate: 5673 – 436 by rounding off the numbers to their greatest places. Also,, find the reasonable estimate.

Solution:

We have, 5673 – 436 = 5237.

The greatest place in 5673 is thousands place and in 436 the greatest place is hundred place.

Estimating 5673 to nearest thousands, we get 6000

Estimating 436 to nearest hundreds, we get 400

Therefore estimated difference = 6000 – 400 = 5600

Clearly, it is not closer to the actual difference. So, it is not a reasonable estimate.

Let us round off 5673 and 436 to nearest hundreds.

5673 rounds off as 5700.

436 rounds off as 400

Therefore estimated difference = 5700 – 400 = 5300


Example 3:

Give a rough estimate and also a closer estimate of 489342 – 48365.

Solution:

We have,

489342 – 48365 = 440877

To find rough estimate, let us round off each number to nearest ten thousands.

489342 rounds off as 490000

48365 rounds off as 50000

Estimates difference = 490000 – 50000 = 440000

So, rough estimate = 440000

In order to obtain a closer estimate, let us round off each number to nearest thousands.

489342 rounds off as 489000

48365 rounds off as 48000

Estimated difference = 489000 – 48000 = 441000

Clearly, it is closer to the actual difference 440977Hence, closer estimate is 441000

Estimate

Estimate to Nearest Tens

Estimate to Nearest Hundreds

Estimate to Nearest Thousands

Estimating Sum and Difference

Estimating Product and Quotient









Numbers Page

6th Grade Page

From Estimating Sum and Difference to HOME PAGE




Didn't find what you were looking for? Or want to know more information about Math Only Math. Use this Google Search to find what you need.



Share this page: What’s this?

Recent Articles

  1. Perimeter of a Rectangle | How to Find the Perimeter of a Rectangle?

    Apr 25, 24 03:45 PM

    Perimeter of a Rectangle
    We will discuss here how to find the perimeter of a rectangle. We know perimeter of a rectangle is the total length (distance) of the boundary of a rectangle. ABCD is a rectangle. We know that the opp…

    Read More

  2. Perimeter of a Square | How to Find the Perimeter of Square? |Examples

    Apr 25, 24 12:54 PM

    Perimeter of a Square
    We will discuss here how to find the perimeter of a square. Perimeter of a square is the total length (distance) of the boundary of a square. We know that all the sides of a square are equal. Perimete…

    Read More

  3. Perimeter of a Triangle | Perimeter of a Triangle Formula | Examples

    Apr 25, 24 12:53 PM

    Perimeter of a Triangle
    We will discuss here how to find the perimeter of a triangle. We know perimeter of a triangle is the total length (distance) of the boundary of a triangle. Perimeter of a triangle is the sum of length…

    Read More

  4. Dividing 3-Digit by 1-Digit Number | Long Division |Worksheet Answer

    Apr 24, 24 03:46 PM

    Dividing 3-Digit by 1-Digit Number
    Dividing 3-Digit by 1-Digit Numbers are discussed here step-by-step. How to divide 3-digit numbers by single-digit numbers? Let us follow the examples to learn to divide 3-digit number by one-digit nu…

    Read More

  5. Symmetrical Shapes | One, Two, Three, Four & Many-line Symmetry

    Apr 24, 24 03:45 PM

    Symmetrical Figures
    Symmetrical shapes are discussed here in this topic. Any object or shape which can be cut in two equal halves in such a way that both the parts are exactly the same is called symmetrical. The line whi…

    Read More