Ratio & Proportion — Sharing Made Easy
✨ IN SHORT — THE WHOLE LESSON IN 20 SECONDS
A ratio compares two quantities like slices of a cake. 2:3 means 5 total parts — first gets 2 parts, second gets 3. Nearly every ratio question is this one idea.
1. Parts & Total
If A:B = 2:3 and total money is ₹500, total parts = 5. One part = 500÷5 = ₹100. A gets 2×100 = ₹200, B gets 3×100 = ₹300. Always: value of one part = total ÷ sum of ratio parts.
📌 Divide ₹840 in 3:4. Parts=7, one part=120. Shares: ₹360 and ₹480.
2. Combining Ratios
If A:B = 2:3 and B:C = 4:5, make B equal: LCM of 3 and 4 is 12. A:B = 8:12, B:C = 12:15 → A:B:C = 8:12:15.
💡 Trick: make the middle number (B) the same in both ratios — then simply join them.
3. Proportion & Mean Proportional
a:b = c:d means a×d = b×c (cross-multiplication). Mean proportional between a and b is √(a×b). Between 4 and 9: √36 = 6.
📌 2:5 = x:20 → 5x = 40 → x = 8.
⚡ Now Practise — 8 Questions
Tap an answer. Right or wrong, we explain why instantly. Learn from every tap!
Q1. Divide ₹600 in the ratio 1:2.
Q2. If A:B = 3:5 and A = 45, B is:
Q3. Ratio of 50 paise to ₹2 (in simplest form) is:
Q4. A:B = 2:3, B:C = 3:4, then A:C is:
Q5. Mean proportional between 9 and 16 is:
Q6. Two numbers are in ratio 5:7. Their sum is 96. The larger number is:
Q7. If x:4 = 9:12, x is:
Q8. Ratio of ages 24 years and 30 years in simplest form:
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