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  • Writer's pictureKritika Daryani

Learn To Solve Ratio And Proportion for CLAT

Updated: Mar 8, 2021


In any kind of competitive exam, the questions involving ratio and proportion are pretty common. It is also very evident from the previous year's papers released by CLAT Consortium that the concept of the ratio is one of the important topics that​​ one must cover in order to fetch marks.​​ If you have gone through the CLAT Consortium’s Sample Paper, you must be aware of the changed pattern of questions in the Quantitative Section. All the questions are in the passage form and multiple questions are asked on the basis of information provided through the various special charts like a pie chart, bar graph, line chart, tables, etc.

It is one of the easiest topics in the Quants section and does not involve very complex formulas or concepts. If two quantities are​​ of the same type, then only they can be expressed as ratios. The ratio is the number of times one quantity contains another. But the type must be the same. You cannot find the ratio between 1 kg of potato and 2 laptops. Ratios are expressed in the form of A: B​​ or A/B ​​ where A is called antecedent and B is called the consequent. When two ratios are equal in value, then they are said to be in proportion. The equivalence of two ratios is called proportion. If a: b = c : d, then a, b, c, d are said to be in proportion. Here, a x d = b​​ x c.

There are a few points with respect to the ratio and proportion that are to be kept in mind while solving the questions of ratio and proportion. Pay attention to these point and keep them in mind while solving the questions relating​​ to ratio and proportion.

  • If p : q = r : s, then p, q, r, s are said to be in proportion. Here, p x s = q x r.

  • ​​ If we have two ratios, say p : q and r : s, then (p x r) : (q x s) is called the compounded ratio.

  • If p : q = r : s, i.e., p/q = r/s, then (p +​​ q) / (p – q) = (r + s) / (r – s) This is called Componendo and Dividendo.

  • If we say that ‘p’ is directly proportional to ‘q’, it means that p = k x q, where ‘k’ is the constant of proportionality.

  • If we say that ‘p’ is inversely proportional to ‘q’, it implies that p = k / q or p x q = k, where ‘k’ is the constant of proportionality

  • If a ratio is multiplied or divided by a certain number, the properties of the ratio do not change. For example, if we multiply 2 : 3 by 7, we get 14 : 21, which is same as 2:3.

As you must be aware that hard work and smart work go hand in hand. Therefore we have to focus our preparation as per the changed pattern in the CLAT Sample paper released by CLAT Consortium on their website. practice one to two daily CLAT mock tests it will boost your confidence. Therefore, there are passage-based questions that involve the concept of Percentage, Average, Ratio, Simple Interest, Compound Interest, Profit & Loss, etc. So, let us focus on the examples given below in order to make sure that we are quick at solving the questions that involve the concept of Ratio and proportion:


Example 1:​​ The ratio of Rice and Pulses in an Indian one-pot dish ‘Khichdi’ is 13: 7. How much rice will be there in 100 kg of Khichdi?

​​ ​​ ​​ ​​ ​​​​ Solution: ​​ This is the simplest and the most direct kind of question. To find​​ How much ​​ ​​​​ rice will be there in 100 kg of Khichdi,

​​ Since, 13+7 = 20

Therefore, ​​ Amount of rice = ( 13/20) *100 ​​ = 65 kg​​


Example 2: A mixture contains artificial blood and orange juice in the ratio 4: 3. If 10 litres of orange juice is added to the mixture, the​​ ratio becomes 4: 5. Find the initial quantity of artificial blood in the given mixture.

Solution: The initial ratio is 4 : 3. Let ‘k’ be the common ratio. => Initial quantity of artificial blood ​​ = 4 k => Initial quantity of orange juice = 3 k =>​​ Final quantity of artificial blood ​​ = 4 k => Final quantity of orange juice = 3 k + 10 Final ratio = 4 k : 3 k + 10 = 4 : 5 => k = 5 Therefore, initial quantity of artificial blood ​​ in the given mixture = 4 k = 20 liters.


Example 3: Three friends Abhilasha​​ , Asad, and Aditi ​​ started a business, each investing Rs. 10,000. After 5 months Abhilasha withdrew Rs. 3000, Asad ​​ withdrew Rs. 2000 and Aditi invested Rs. 3000 more. At the end of the year, there was a total profit of Rs. 34,600. Find the share of Abhilasha, Asad, and Aditi ​​ separately. Solution:​​ We know that if the period of investment is not uniform, the gains/losses from the business are divided in the ratio of their inputs, where input is calculated as the product of the amount of investment and time period of investment. So, input = value of investment x period of investment, and here, the period of investment would be broken into parts as the investment is not uniform throughout the time period. Abhilasha’s input = (10,000 x 5) + (7,000 x 7) = 99,000 Asad’s​​ input = (10,000 x 5) + (8,000 x 7) = 1,06,000 Aditi’s input = (10,000 x 5) + (13,000 x 7) = 1,41,000 => Abhilasha : Asad : Aditi = 99000 : 106000 : 141000 => Abhilasha : Asad : Aditi = 99 : 106 : 141 => Abhilasha : Asad : Aditi = (99 / 346) : (106 / 346)​​ : (141 / 346) Thus, Abhilasha’s share = (99 / 346) x 34600 = Rs. 9900 Asad’s share = (106 / 346) x 34600 = Rs. 10600 Aditi’s share = (141 / 346) x 34600 = Rs. 14100


You can also buy test series for clat 2021 for more questions in every subject.

Example 4:​​ In a certain government department, the ratio of male employees to female employees is 7: 5. If there are 2400 employees in the department, then how many female employees are there?

Solution:​​ Let the number of male employees and female employees are 7x and 5x, respectively. Given, total number of employees = 2400 ⇒​​ 7x + 5x = 2400 ​​ ⇒ 12x = 2400 x = 200 ∴​​ number of female employees = 5x = 5 × 200 = 1000


Example 5: 5 bottles as much as 12 tiffins, 7 tiffins as much as 2 boxes, 3 boxes as many as 2 bags. If the cost of 5 bags is Rs 875, then find the cost of a bottle. Solution:​​ 5​​ bags = 875 2 bags = 875 * 2/5 = 3 box 2 box cost= 875 * 2/5 * 2/3 = 7 tiffin cost 12 tiffin cost = 875 * 2/5 * 2/3 * 12/7 = 5 bottles 1 bottle = 875 * 2/5 * 2/3 * 12/7 * 1/5 =​​ Rs 80


Example 7:​​ The ratio of the age of Mayank and his Priyanshi is 6:5. After​​ 16 years, the ratio becomes 10:9. Find Mayank’s age when the Priyanshi was born. Solution:​​ Let x is Mayank’s age And y is the Priyanshi’s age. x/y= 6/5 x=(6/5)y

After 16 years, (x + 16)/(y + 16) = 10/9 9x + 144 = 10y + 160 9*(6/5)y = `10y + 16 54y – 50y =​​ 80 y=20 Then x = 24 When Priyanshi was born Mayank’s age =​​ 4 years.


I am Judge by profession. Practice previous year papers and Mock tests prepare well. else you can join clat coaching in Bangalore for better preparations

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