Jod aur Antar ke Multiples

Class 7 Maths · Chapter 2: Arithmetic Expressions · NCERT Ganita Prakash section 2.2

Seekho

Do dost har ek dosa (₹43) aur lassi (₹24) lete hain. Kya total 2 × 43 + 24 hai? Nahi, iska matlab 2 × 43 se 24 zyaada. Hume (43 + 24) ka double chahiye, isliye bracket: 2 × (43 + 24) = 2 × 67 = ₹134. Ye do dose aur do lassi bhi hai: 2 × 43 + 2 × 24 = 86 + 48 = ₹134.

2 × (43 + 24) = 2 × 43 + 2 × 24

Parade ki kataarein: 5-5 scouts ki 4 kataarein aur 5-5 guides ki 3: 4 × 5 + 3 × 5 = 35. Ya pehle kataarein gino: (4 + 3) × 5 = 7 × 5 = 35. Jod ka multiple = multiples ka jod: 10 × 98 + 3 × 98 = 13 × 98. Antar ke liye bhi: 14 × 10 − 6 × 10 = (14 − 6) × 10 = 80.

4 × 5 + 3 × 5 = (4 + 3) × 5 = 35

Jaldi ke guna: 97 × 25 = (100 − 3) × 25 = 2500 − 75 = 2,425. Aur 104 × 15 = 1500 + 60 = 1,560. Agar pata hai 53 × 18 = 954, to 63 × 18 = 954 + 10 × 18 = 954 + 180 = 1,134. Number ko aasaan hisse aur thode se jod (ya ghata) mein todo.

97 × 25 = 100 × 25 − 3 × 25 = 2,425

Dhyaan do: 5 × 4 + 3 aur 5 × (4 + 3) ek nahi. Pehla 23 (20 se 3 zyaada); doosra 35 (7 ka 5 guna). Bracket tay karta hai ki kya multiply hoga. Aur (8 − 3) × 29 > (3 − 8) × 29, kyunki 5 × 29 positive aur (−5) × 29 negative hai.

5 × 4 + 3 = 23 but 5 × (4 + 3) = 35

Explore: multiply karne ke jaldi tareeke.

1. Har guna ko uske jaldi wale roop se milaao.

Yaad rakho

• a × (b + c) = a × b + a × c aur a × (b − c) = a × b − a × c.
• 10, 100 ya 1000 ke paas wale number ko todkar jaldi multiply karo: 97 × 25 = 2500 − 75.

Quick check

Khaali jagah bharo: 3 × (5 + 8) = 3 × 5 + 3 × ___

1. 8
2. 5
3. 3
4. 13

Socho

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Practice

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