Ncert Solutions For Class 6 Maths Ex 1.3

Ncert Solutions For Class 6 Maths Chapter 1 Ex 1.3

QUESTIONS 1:

Determine the following by using general rule:

(i) 768 + 830

(ii) 596 – 340

(iii) 5432 + 3129

(iv) 24850 – 22720

Answer:

(i) 768 rounding off to 800

830 rounding off to 800

Estimated sum = 1600

 

(ii) 596 rounding off to 600

340 rounding off to 300

Estimated difference = 300

 

(iii) 5432 rounding off to 5000

3129 rounding off to 3000

Estimated sum = 8000

 

(iv) 24850 rounding off to 25000

22720 rounding off to 23000

Estimated difference= 2000

 

Question 2:

Estimate the following (by rounding off the values to nearest hundreds) and a closer estimate (by rounding off to nearest tens):

(i) 440 + 324 + 4650

(ii) 1,08,747 – 47,593

(iii) 8235 – 392

(iv) 4,89,338 – 48,375

Answer:

(i) 440 rounding off to 400

324 rounding off to 300

4650 rounding off to 4700

Estimated sum = 5400

 

(ii) 108747 rounding off to 108700

47593 rounding off to 47600

Estimated difference = 61100

(iii) 8235 rounding off to 8200

392 rounding off to 400

Estimated difference = 7800

 

(iv) 489338 rounding off to 489300

48375 rounding off to 48400

Estimated difference = 440900

 

 

Question 3:

Determine the following by using general rule:

(i) 568 x 180

(ii) 4280 x 2490

(iii) 1190 x 589

(iv) 5270 x 29

Answer:

(i) 568 x 180

568 rounding off to 600

180 rounding off to 200

The estimated product = 600 x 200 = 1,20,000

 

(ii) 4280 x 2490

4280 rounding off to 4300

2490 rounding off to 2500

The estimated product = 4300 x 2500 = 1,07,50,000

 

(iii) 1190 x 589

1190 rounding off to 1200

589 rounding off to 600

The estimated product = 1200 x 600 = 7,20,000

 

(iv) 5270 x 29

5270 rounding off to 5500

29 rounding off to 30

The estimated product = 5500 x 30 = 1,65,000