Adla-badli aur Grouping

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

Seekho

Ek drone 6 m upar jaata hai phir 4 m neeche: uski oonchaai 6 − 4 = 6 + (−4) = 2 m. Terms badlo: (−4) + 6 = 2, wahi. Do terms ki adla-badli se jod kabhi nahi badalta, negative numbers ke saath bhi. Ise jod ka commutative property kehte hain.

6 + (−4) = (−4) + 6 = 2

Grouping: (−7) + 10 + (−11) mein pehle do jodo: 3 + (−11) = −8. Ya aakhri do pehle: (−7) + (−1) = −8. Wahi jawab! Grouping se jod nahi badalta: associative property. Dono ko milaakar, terms ko kisi bhi kram mein jod sakte hain.

(−7) + 10 + (−11) = −8 in any order

Kyun kaam ka: tumne lambi list joda aur 11,749 aaya, par 9,055 jodna bhool gaye. Dobara shuru karne ki zaroorat nahi: bas total mein jodo, 11,749 + 9,055 = 20,804, kyunki jodne ka kram maayne nahi rakhta. Aasaan jode pehle jodo: 37 + 48 + 63 = (37 + 63) + 48 = 148.

37 + 48 + 63 = (37 + 63) + 48 = 148

Roz ki zindagi mein kram: "Topi aur joote pehno": kisi bhi kram mein, tum ek jaise dikhoge. "Moze aur joote pehno": kram maayne rakhta hai! Maths mein jodna topi-joote jaisa hai, par ghataana nahi: 10 − 3 = 7, jabki 3 − 10 = −7.

10 − 3 = 7 but 3 − 10 = −7

Explore: kya kram maayne rakhta hai?

1. Har kaam sort karo.

Yaad rakho

• Terms ki adla-badli ya alag grouping se jod kabhi nahi badalta.
• Pehle ghataav ko negative terms mein badlo; phir kisi bhi kram mein jodo.

Quick check

Kaunsa 87 + 46 − 109 ke barabar hai?

1. 46 − 109 + 87
2. 87 − 46 + 109
3. 87 − (46 + 109)
4. 109 − 87 + 46

Socho

1 − 2 + 3 − 4 + 5 − 6 + 7 − 8 + 9 − 10 ko chaalaaki se jodo.

Practice

Teen levels (easy, medium, hard) ke naye sawaalon se practice karo, kuch hands-on, hints aur hal ke saath. Topic poora karne ke liye pichhle 5 mein se 4 sahi karo.