# Give a rough estimate (by rounding off to nearest hundreds) and also a closer estimate (by rounding off to nearest tens):

(a) 439 + 334 + 4317 (b) 108734 - 47599 (c) 8325 - 491 (d) 489348 - 48365.

Make four more such examples.

**Solution:**

We will be using the concept of Estimation in Maths to solve this problem.

**(a)** 439 + 334 + 4317

Round off of 439 to nearest hundreds = 400

Round off of 334 to nearest hundreds = 300

Round off of 4317 to nearest hundreds = 5000

Sum of 439 + 334 + 4317 = 400 + 300 +4300 = 5000

Rounding off to nearest tens

Rounding off to nearest ten of 439 = 440

Rounding off to nearest ten of 334 = 330

Rounding off to nearest ten of 4317 = 4320

Sum of (439 + 334 + 4317) to nearest ten = 440 + 330 + 4320 = 5090

**(b)** 108734 - 47599

Round off of 108734 to nearest hundreds = 108700

Round off of 47599 to nearest hundreds = 47600

Difference of (108734 - 47599) to nearest hundreds = 108700 - 47600 = 61100

Rounding off to nearest tens

Rounding off to nearest ten of 108734 = 108730

Rounding off to nearest ten of 47599 = 47600

Rounding off to nearest ten of difference of (108734 - 47599) = 108730 - 47600 = 61130

**(c)** 8325 - 491

Round off to nearest hundreds is (8325 - 491) = (8300 - 500) = 7800

On rounding off to nearest tens we get (8325 - 491) = 8330 - 490 = 784

**(d)** 489348 - 48365

Round off to nearest hundreds is (489348 - 48365) = 489300 - 48400 = 440900

On rounding off to nearest tens we get (489348 - 48365) = 489350 - 48370 = 440980

Four more examples are as follows

(i) 4856 + 661

Rounding off to nearest hundreds

4856 + 661 = 4800 + 700 = 5500

Rounding off to nearest tens

4856 + 661 = 4850 + 660 = 5510

(ii) 772 - 389

ounding off to nearest hundreds

772 - 389 = 800 - 400 = 400

Rounding off to nearest tens

772 - 389 = 780 - 390 = 390

(iii) 6365 - 2865

Rounding off to nearest hundreds

6365 - 2865 = 6400 - 2900 = 3500

Rounding off to nearest tens

6365 - 2865 = 6370 - 2870 = 3500

(iv) 8245 - 6313

Rounding off to nearest hundreds

8245 - 6313 = 8200 - 6300

= 1900

Rounding off to nearest tens

8245 - 6313 = 8240 - 6310

= 1930

NCERT Solutions Class 6 Maths - Chapter 1 Exercise 1.3 Question 2

## Give a rough estimate (by rounding off to nearest hundreds) and also a closer estimate (by rounding off to nearest tens):(a) 439 + 334 + 4317 (b) 108734 - 47599 (c) 8325 - 491 (d) 489348 - 48365. Make four more such examples

**Summary:**

(a) 439 + 334 + 4317 c rounded off to nearest ten = 440 + 330 + 4320 = 5090 (b) 108734 - 47599 rounded off to nearest ten = 108730 - 47600 = 61130 (c) 8325 - 491 rounded off to nearest ten = 8330 - 490 = 784 (d) 489348 - 48365 rounded off to nearest ten = 489350 - 48370 = 440980