NCERT Solutions Class 6 Maths Chapter 1 Knowing Your Numbers Exercise 1.3 are provided here. These solutions are prepared by expert teachers to guide you in your exam preparation. The solutions are always prepared by following NCERT guidelines, so that it covers the whole syllabus accordingly. Our CBSE Class 6 Maths Solutions Chapter 1 Exercise 1.3 Solutions are very helpful in scoring well in examinations.
NCERT Solutions for Class 6 Maths Chapter 1 Exercise 1.3
EXERCISE 1.3
Question 1: Estimate each of the following using general rule:
(a) 730 + 998
(b) 796 – 314
(c) 12,904 + 2,888
(d) 28,292 – 21,496
Make ten more such examples of addition, subtraction and estimation of their outcome.
Answer:
(a) 730 + 998
Round off to hundreds
730 rounds off to 700
998 rounds off to 1000
Hence, 730 + 998 = 700 + 1000 = 1700
(b) 796 – 314
Round off to hundreds
796 rounds off to 800
314 rounds off to 300
Hence, 796 – 314 = 800 – 300 = 500
(c) 12904 + 2888
Round off to thousands
12904 rounds off to 13000
2888 rounds off to 3000
Hence, 12904 + 2888 = 13000 + 3000 = 16000
(d) 28292 – 21496
Round off to thousands
28292 round off to 28000
21496 round off to 21000
Hence, 28292 – 21496 = 28000 – 21000 = 7000
Ten more such examples are
(i) 330 + 280 = 300 + 300 = 600
(ii) 3937 + 5990 = 4000 + 6000 = 10000
(iii) 6392 – 3772 = 6000 – 4000 = 2000
(iv) 5440 – 2972 = 5000 – 3000 = 2000
(v) 2175 + 1206 = 2000 + 1000 = 3000
(vi) 1110 – 1292 = 1000 – 1000 = 0
(vii) 910 + 575 = 900 + 600 = 1500
(viii) 6400 – 4900 = 6000 – 5000 = 1000
(ix) 3731 + 1300 = 4000 + 1000 = 5000
(x) 6485 – 4319 = 6000 – 4000 = 2000
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 + 4,317
(b) 1,08,734-47,599
(c) 8,325-491
(d) 4,89,348-48,365
Make four such examples:
Answer: (a) 439 + 334 + 4,317
Rough estimate (Rounding off to nearest hundreds)
439 + 334 + 4,317 = 400 + 300 + 4300 = 5,000
Closer estimate (Rounding off to nearest tens)
439 + 334 + 4317 = 440 + 330 + 4320 = 5090.
(b) 1,08,734 – 47,599
Rough estimate (Rounding off to nearest hundreds)
1,08,734 – 47,599 = 1,08,700 – 47,600 = 61,100
Closer estimate (Rounding off to nearest tens)
1,08,734 – 47,599 = 1,08,730 – 47,600 = 61,130.
(c) 8325 – 491
Rough estimate (Rounding off to nearest hundreds)
8325 – 491 = 8300 – 500 = 7800
Closer estimate (Rounding off to nearest tens)
8325 – 491 = 8330 – 490 = 7840.
(d) 4,89,348 – 48,365
Rough estimate (Rounding off to nearest hundreds)
4,89,348 – 48,365 = 4,89,300 – 48,400 = 4,40,900
Closer estimate (Rounding off to nearest tens)
4,89,348 – 48,365 = 4,89,350 – 48,370 = 4,40,980
Example 1:
384 + 562
Solution:
Rough estimate (Rounding off to nearest hundreds)
384 + 562 = 400 + 600
= 1,000
Closer estimate (Rounding off to nearest tens)
384 + 562 = 380 + 560
= 940
Example 2:
8765 – 3820
Solution:
(i) Rough estimate (Rounding off to nearest hundreds)
8765 – 3820 = 8800 – 3900
= 4900
(ii) Closer estimate (Rounding off to nearest tens)
8765 – 3820 = 8770 – 3820
= 4950
Example 3:
6653 + 8265
Solution:
Rough estimate (Rounding off to nearest hundreds)
6653 + 8265
= 6700 + 8300
= 15,000
Closer estimate (Rounding off to nearest tens)
6653 + 8265
= 6650 + 8270
= 14920
Example 4:
3826 – 1262
Solution:
Rough estimate (Rounding off to nearest hundreds)
3826 – 1262
= 3800 – 1300
= 2500
Closer estimate (Rounding off to nearest tens)
3826 – 1262
= 3830 – 1260
= 2570
Question 3: Estimate the following products using general rule:
(a) 578 × 161
(b) 5281 × 3491
(c) 1291 × 592
(d) 9250 × 29
Answer: (a) 578 × 161
578 round off to 600 161 round off to 200
The estimated product = 600 × 200 = 1,20,000
(b) 5281 × 3491
5281 round of to 5,000
3491 round off to 3,500
The estimated product = 5,000 × 3,500 = 1,75,00,000
(c) 1291 × 592
1291 round off to 1300
592 round off to 600
The estimated product = 1300 × 600 = 7,80,000
(d) 9250 × 29
9250 round off to 10,000
229 round off to 30|
The estimated product = 10,000 × 30 = 3,00,000
Access NCERT Solutions for Class 6 Maths Chapter 1 Knowing Your Numbers – All Exercises
Below we have provided the links to check solutions of the other exercises of the chapter.