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E:\Working\Focus_Learning\Math_Genius_5_(05-10-2023)\Open_Files\CHAP_02
\\February 27, 2024 10:04 AM Surender Prajapati Proof 5 Reader _________________________ Date: ___________________74

example 3: A godown has 10359 maize sacks. If each sack contains 175 kg of maize, then
what quantity of maize is in all the sacks?

Solution: Number of maize sacks in the godown = 10359 tL L tth th H t O
Weight of one sack of maize = 175 kg 1 0 3 5 9
Therefore, the total weight of maize = (10359 × 175) kg × 1 7 5

= 1812825 kg 5 1 7 9 5
7 2 5 1 3 0
+ 1 0 3 5 9 0 0

1 8 1 2 8 2 5
Properties of multiplication

1. Numbers can be multiplied in any order. The product will remain the same. It is called
order property of multiplication.
example: 3354 × 6 = 6 × 3354 = 20124

2. When a number is multiplied by 1, the product is the number itself.
example: 7824 × 1 = 7824 and 9878 × 1 = 9878
3. When a number is multiplied by 0, the product is always 0.

example: 493 × 0 = 0 and 9643 × 0 = 0
4. The product of three numbers does not change when the grouping of numbers is
changed. It is called grouping property of multiplication.
example: (16 × 12) × 15 = (16 × 15) × 12 = (12 × 15) × 16 = 2880.

5. If a sum or a difference of two numbers is multiplied by another number, they can be
multiplied separately and then added or subtracted.
examples: (a) (12 + 5) × 10 = 17 × 10 = 170
or (12 + 5) × 10 = (12 × 10) + (5 × 10)

= 120 + 50 = 170
(b) (12 – 5) × 10 = 7 × 10 = 70
or (12 – 5) × 10 = (12 × 10) – (5 × 10)

= 120 – 50 = 70

Practice time 2c

1. Find the product.

(a) 2563 × 123 (b) 8905 × 236 (c) 7894 × 306 (d) 48792 × 216
(e) 16247 × 532 (f) 4578 × 1245 (g) 3486 × 2475 (h) 14018 × 1045

2. Find the product without actual multiplication.

(a) 7557 × 10 = ______ (b) 78051 × 100 = ______ (c) 4655 × 100 = ______
(d) 97435 × 100 = ______ (e) 7263 × 100 = ______ (f) 5090 × 1000 = ______

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