Page 31 - Maths Class 06

For example, (16 ÷ 8) ÷ 2 = 2 ÷ 2 = 1 NOTE
16 ÷ (8 ÷ 2) = 16 ÷ 4 = 4 Division by zero is defined.
Therefore, (16 ÷ 8) ÷ 2 ¹ 16 ÷ (8 ÷ 2).

Hence, the division of whole numbers is not associative as well.
Prop erty 7.
NOTE
Operations of multiplication and division are inverse of each other.
One single multiplication fact
For example, 6 ÷ 2 = 3 and 3 × 2 = 6
gives two division facts.
6 ÷ 3 = 2 and 2 × 3 = 6

Multiplication fact Corresponding division fact

10 × 2 = 20 20 ÷ 2 = 10, 20 ÷ 10 = 2
5 × 6 = 30 30 ÷ 6 = 5, 30 ÷ 05 = 6
4 × 6 = 24 24 ÷ 6 = 4, 24 ÷ 04 = 6

But when a whole number is not divided by another whole number completely, then some remainder is
obtained.

Exercise 2.2

1. Fill in the blanks:
(a) 5 + ( 105 + 2 =) ( 5 + _____ ) + 2 (b) _____ + 515 = 515
(c) 1275 1¸ = ________ (d) 5 92 20´ ´ = _______ ´ 92
(e) 195 ´ _____ = 405 ´ ____ (f) 7 0´ = _______ = 0 ´ _______

(g) 751 751¸ = ______
(h) 128 ´( 100 2- ) = 128 ´ ______ - 128 ´ ______
2. Find the sum using suitable rearrangement of numbers:
(a) 266 + 508 + 234 (b) 205 + 196 + 104 + 95

(c) 521 + 378 + 79 + 122
3. Verify the associative prop erty of addition for the following numbers:
(a) 2, 4, 6 (b) 3, 5, 7
4. Find the product using associative prop erty of numbers:

(a) 125 799´ ´ 4 (b) 50 ´ 29 ´ 80
(c) 4 572 50´ ´ (d) 625 777 16´ ´
5. Simplify the following:
(a) 1008 8´ + 1008 92´ (b) 562 ´ 4 80´ + 281 20´ ´ 8 ´ 4
(c) 952 15´ - 5 952´ (d) 697 25 282´ ´ + 3485 5 718´ ´

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