Whole Numbers Class 6 Ex. 2.3
Ncert Class 6 Math Free Solution.
Exercise 2.3
Question 1 :- Which of the following will not represent zero. ?
(a) 1 + 0
(b) 0 x 0
(c) 0/2
(d) (10−10)/2
Solution 1:-
(a) 1 + 0 = 1 ≠ 0 ( does not represent zero.
(b) 0 x 0 = 0, ( represents zero
(c) 0/2 = 0, ( represents zero.
(d) (10−10)/2 = 0/2 = 0 ( represents zero ).
Question 2 :- f the product of two whole numbers is zero, can we say that one or both of them will be zero? Justify through examples.
Solution 2:-
Yes,
Examples :-
7 x 0 = 0
0 x 6 = 0
0 x 0 = 0
Question 3 :- If the product of two whole numbers is 1, can we say that one or both of them will be 1? Justify through examples.
Solution 3:-
Only when all of the numbers are 1 is this true.
1 x 1 = 1
1 x 0 = 0
0 x 1 = 0
So, condition only true, when each of the number are 1.
Question 4. Find using distributive property :
(а) 728 x 101
(b) 5437 x 1001
(c) 824 x 25
(d) 4275 x 125
(e) 504 x 35
Solution 4:-
(a) 728 x 101 = 728 x (100 + 1)
= 728 x 100 + 728 x 1
= 72800 + 728
= 73,528
(b) 5437 x 1001 = 5437 x (1000 + 1)
= 5437 x 1000 + 5437 x 1
= 54,37,000 + 5,437
= 54,42,437
(c) 824 x 25 = 824 x (20 + 5)
= 824 x 20 + 824 x 5
= 16480 + 4120
= 20,600
(d) 4275 x 125 = 4275 x (100 + 20 + 5)
= 4275 x 100 + 4275 x 20 + 4275 x 5
= 427500 + 85500 + 21375
= 5,34,375
(e) 504 x 35 = (500 + 4) x 35
= 500 x 35 + 4 x 35
= 17500 + 140
= 17,640
Question 5:- Study the pattern :-
1 x 8 + 1= 9
12 x 8 + 2 = 98
123 x 8 + 3 = 987
1234 x 8 + 4 = 9876
12345 x 8 + 5 = 98765
Write the next two steps. Can you say how the pattern works?
Solution 5:-
Step I: 123456 x 8 + 6 = 987654
Step II: 1234567 x 8 + 7 = 9876543
Working pattern:
(1) x 8 + 1 = 9
(12) x 8 + 2 = (11 + 1) x 8 + 2 = 98
(123) x 8 + 3 = (111 + 11 + 1) x 8 + 3 = 987
(1234) x 8 + 4 = (1111 + 111 + 11 + 1) x 8 + 4 = 9876
(12345) x 8 + 5 = (11111 + 1111 + 111 + 11 + 1) x 8 + 5 = 98,765.