1.1.12 · Maths › Arithmetic & Number Systems
Ek fraction sirf yeh likhne ka tarika hai ki "mere paas kitne equal pieces hain, us total se jisme ek whole banta hai." Neeche wala number har piece ki size batata hai; upar wala number pieces ko count karta hai. Jab yeh sach mein samajh aa jaye, toh "proper", "improper" aur "mixed" bas teen alag costumes hain jo ek hi amount pehenta hai.
Ek fraction b a (jahan b = 0 ) ka matlab hai: ek whole ko b equal parts mein tod lo (denominator ), phir unme se a parts lo (numerator ).
Numerator a = kitne parts count karte ho.
Denominator b = kitne parts milke ek whole banta hai (part ka size).
b = 0 kyun? 0 equal parts mein baantna meaningless hai — koi "piece size" hi nahi hai jo count ho sake, isliye yeh symbol undefined hai.
Definition Proper, Improper, Mixed
Ek proper fraction mein numerator denominator se chhota hota hai: ∣ a ∣ < ∣ b ∣ , jaise 4 3 . Iski value − 1 aur 1 ke beech hoti hai — ek whole se kam .
Ek improper fraction mein numerator ≥ denominator hota hai: ∣ a ∣ ≥ ∣ b ∣ , jaise 4 7 . Iski value ek whole ya usse zyada hoti hai.
Ek mixed number ek improper fraction ko whole part + proper fraction ke roop mein likhta hai, jaise 1 4 3 .
Intuition "Improper" galat kyun nahi hai
"Improper" ka matlab galat nahi hai — 4 7 bilkul valid hai. Iska bas yeh matlab hai ki upar wala "overflow" ho gaya ek pure whole se aage. Mixed numbers us overflow ko ek visible whole number mein nikaal dete hain taaki insaan use jaldi picture kar sake.
Derivation, step by step:
a = q b + r — Kyun? Har integer a ko b ke pure groups mein plus ek leftover r (jo b se chhota hai) mein split kiya ja sakta hai. Yahi quotient & remainder ki definition hai.
Fraction split karo: b q b + r = b q b + b r — Kyun? Kyunki b x + y = b x + b y (division addition ke upar distribute hoti hai).
b q b = q — Kyun? q b ko b -sized pieces mein divide karne par exactly q whole groups milte hain.
Toh value hai q wholes plus proper leftover b r .
Yeh kaam kyun karta hai: yeh literally upar wali derivation ka reverse hai — q wholes ko common denominator b ke upar wapas rakho aur parts add karo.
Recall Forecast: bina divide kiye, kya
7 100 14 ke zyada kareeb hai ya 15 ke?
14 × 7 = 98 , 15 × 7 = 105 . Kyunki 100 sirf 2 upar hai 98 se, 7 100 = 14 7 2 — 14 ke zyada kareeb. Verify: 14 ⋅ 7 + 2 = 100 ✓.
2 4 3 ka matlab 2 × 4 3 hai"
Kyun sahi lagta hai: algebra mein, do symbols side by side (2 x ) multiply karne ka matlab hota hai. Fix: mixed-number notation ek special addition shorthand hai: 2 4 3 = 2 + 4 3 . Whole ko fraction se kabhi multiply mat karo.
Common mistake Mixed → improper convert karte waqt whole × denominator ki jagah numerator ko whole mein add karna
4 8 3 = 8 4 + 3 = 8 7 likhna. Kyun tempt karta hai: tum "upar ke numbers combine" kar rahe ho. Fix: 4 wholes ko pehle eighths mein convert karna padega (4 × 8 = 32 ) phir 3 add karo. Sahi: 8 35 .
Common mistake Yeh sochna ki
4 7 "galat" hai aur hamesha mixed banana chahiye
Kyun sahi lagta hai: textbooks aksar mixed answers maangti hain. Fix: improper fractions bilkul valid hain aur multiply/divide karne mein aasaan hote hain. Mixed mein sirf tab convert karo jab specifically kaha jaye ya intuition ke liye.
Recall Feynman: ek 12-saal ke baache ko explain karo
Imagine karo pizzas jo 4 slices mein kati hain. Agar tumhare paas 3 slices hain, yeh ek pizza se kam hai — ek proper fraction 4 3 . Agar tumhare paas 7 slices hain, yeh ek pizza se zyada hai — ek improper fraction 4 7 . Lekin yeh kehna zyada friendly hai "1 pura pizza aur 3 slices baaki" — yahi mixed number 1 4 3 hai. Pizza ki same amount, bas alag tarike se describe ki gayi!
Mnemonic Direction yaad rakho
"Mixed → improper: Multiply Bottom, Add Top" (MBAT). Aur "Improper → mixed: Divide, and the Remainder Rides on top."
What does the denominator of a fraction tell you? Kitne equal parts milke ek whole banta hai (har part ka size).
What is a proper fraction? Woh jiska numerator denominator se chhota ho (value −1 aur 1 ke beech).
What is an improper fraction? Numerator ≥ denominator; value ek whole ya usse zyada.
How do you convert an improper fraction a/b to a mixed number? a ko b se divide karo; quotient whole part hai, remainder ko b ke upar rakho fraction part ke liye.
Convert 17/5 to a mixed number. 3 2/5 (kyunki 17 = 3×5 + 2).
Convert 4 3/8 to an improper fraction. 35/8 (kyunki 4×8 + 3 = 35).
Why can't a denominator be 0? 0 equal parts mein baantna undefined hai — koi piece size nahi hai.
Does "improper" mean the fraction is wrong? Nahi — yeh valid hai, bas ≥ 1 whole hai. Mixed form sirf readability ke liye hai.
Rule to go mixed → improper? (whole × denominator) + numerator, sab denominator ke upar.
Division with remainder — improper→mixed conversion ka engine.
Equivalent fractions — same value, alag numerator/denominator.
Adding and subtracting fractions — common denominator chahiye.
Decimals — same quantity likhne ka aur ek tarika.
Ratios and proportions — fractions disguise mein.
Number line — jahan proper (0–1 ke andar) aur improper (1 se aage) fractions baithe hain.
classified by comparing a and b
whole times denom plus num
Whole part plus proper part