📘 BANK EXAM SPEED MATHS – PAGE 8

🔹 Average & Mixture Tricks

Average and mixture problems are common in bank exams and are often used in data interpretation and arithmetic sections. Using shortcut methods can help solve these quickly.

✅ Trick 1: Average Formula

Formula: Average = Total Sum ÷ Number of Items

Example: Average of 10, 20, 30, 40, 50

• Total = 150
• Number of items = 5
• Average = 150 ÷ 5 = 30

---

✅ Trick 2: Shortcut for Equal Interval Numbers

Concept: Average = Middle number

Example: 10, 20, 30, 40, 50

• Middle value = 30

---

✅ Trick 3: Weighted Average (Mixture)

Example: Mix 10 kg at ₹20/kg and 20 kg at ₹30/kg

• Total cost = (10×20) + (20×30) = 200 + 600 = 800
• Total quantity = 30 kg
• Average price = 800 ÷ 30 = 26.67

---

✅ Trick 4: Alligation Method (Fast Mixture)

Example: Mix ₹20/kg and ₹30/kg to get ₹25/kg

• Ratio = (30 − 25) : (25 − 20)
• = 5 : 5 = 1 : 1

---

🔹 Practice Questions

1. Find average of 15, 25, 35, 45
2. Average of first 10 natural numbers = ?
3. Mix 5 kg at ₹40 and 5 kg at ₹60, find average price
4. Alligation: ₹10 and ₹20 to get ₹15, find ratio
5. Average of 5 consecutive numbers starting from 6 = ?

🔹 Exam Tips

✔ Use middle value shortcut for equally spaced numbers
✔ Apply alligation method for faster mixture solving
✔ Avoid long calculations in average questions
✔ Practice mental calculation regularly

---

Shaktimatha Learning © 2026 | Bank Exam Preparation Series