Short Trick to Divide a Given Number X in ratio of M N
Duration: 16 min
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This lecture teaches a shortcut for dividing a given number x in the ratio m:n by first finding the value of one part and then multiplying it by each ratio term. The instructor opens with a definition of ratio as the comparison of two quantities, noting that it can be written in colon, word, or fraction form. The main method is introduced as “Dividing a given number 'x' in the ratio 'm:n'.” A story-based example uses Suresh and Mahesh, with a 153 lakh property to be divided in the ratio 4:5. The total number of parts is found as 4 + 5 = 9, so one part equals 153/9 = 17 lakh. Suresh’s share is then calculated as 4 × 17 = 68 lakh, and Mahesh’s share as 5 × 17 = 85 lakh. The instructor verifies the answer by adding the two shares back to 153 lakh. A second example involves Jethalal, Sunderlal, and Taarak Bhai sharing a profit of Rs. 10,85,000 in the efficiency ratio 7:11:13. The total number of parts is 7 + 11 + 13 = 31, so one part equals 10,85,000/31 = Rs. 35,000. Sunderlal’s share is highlighted as 11 × 35,000 = Rs. 3,85,000. A third example introduces chained ratios: Rs. 200 is divided among Neha, Tony, and Sonu such that N:T = 2:3 and T:S = 3:5. The instructor combines these into a single ratio N:T:S = 2:3:5, giving 10 parts equal to 200. One part is therefore 20, so Neha’s share is 2 × 20 = 40 and Tony’s share is 3 × 20 = 60. The final example extends the chained-ratio method to four people: Rs. 5000 is divided among Guddu, Munna, JP Yadav, and Kaleen Bhaiya with ratios G:M = 1:2, M:J = 2:3, and J:K = 3:4. These are combined into G:M:J:K = 1:2:3:4, giving 10 parts equal to 5000. One part is 500, so Munna’s share is 2 × 500 = Rs. 1000, which is circled as the answer. The lesson ends with a “THANKS FOR WATCHING” screen.
Chapters
0:00 – 2:00 00:00-02:00
The video opens with a slide titled “RATIO & PROPORTION” that defines ratio as “a comparison of 2 quantities” and states it can be written in colon, word, or fraction form. The instructor then introduces the specific topic: “Dividing a given number 'x' in the ratio 'm:n'.” A “Story Time” segment begins with an illustration of three men, two of whom are labeled “Suresh” and “Mahesh,” followed by a house illustration labeled “Father.” This sets up the contextual word problem that will be solved using the ratio-division shortcut.
2:00 – 5:00 02:00-05:00
The story problem is formalized as “153 lakh property into two parts in the ratio 4:5,” with Suresh associated with 4 and Mahesh with 5. The instructor writes “153 -> 9 parts” and “9 parts -> 153 lakh,” then calculates one part as 153/9 = 17 lakh. The individual shares are found by multiplying: “Suresh -> 4 x 17 lakh = 68 lakh” and “Mahesh -> 5 x 17 = 85 lakh.” A verification step adds the two shares back to confirm they total 153 lakh, reinforcing that the parts must sum to the original amount.
5:00 – 10:00 05:00-10:00
A partnership problem is presented in an orange panel: Jethalal, Sunderlal, and Taarak Bhai have an efficiency ratio of 7:11:13 and a total profit of Rs. 10,85,000. The instructor labels the ratio as “Bhag ← efficiency ratio” and computes the total parts: 7 + 11 + 13 = 31. One part is then found as 10,85,000/31 = Rs. 35,000. Each partner’s share is obtained by multiplying their ratio term by 35,000; Sunderlal’s share of 11 × 35,000 = Rs. 3,85,000 is circled as the answer. This example demonstrates applying the same one-part method to a three-way division.
10:00 – 15:00 10:00-15:00
The lesson moves to chained ratios. First, Rs. 200 is divided among Neha, Tony, and Sonu with N:T = 2:3 and T:S = 3:5. The instructor writes the fractions N/T = 2/3 and T/S = 3/5, then combines them into the single ratio N:T:S = 2:3:5. Since 2 + 3 + 5 = 10 parts equal 200, one part is 20. Neha’s share is calculated as 2 × 20 = 40 and Tony’s as 3 × 20 = 60. A second chained-ratio problem then introduces Rs. 5000 divided among Guddu, Munna, JP Yadav, and Kaleen Bhaiya with G:M = 1:2, M:J = 2:3, and J:K = 3:4.
15:00 – 15:30 15:00-15:30
The final chained-ratio problem is completed. The ratios G:M = 1:2, M:J = 2:3, and J:K = 3:4 are combined into G:M:J:K = 1:2:3:4, giving 1 + 2 + 3 + 4 = 10 parts equal to 5000. One part is therefore 500, and the four shares are labeled 500, 1000, 1500, and 2000. Munna’s share of (2/10) × 5000 = Rs. 1000 is circled as the answer, and the video ends with a “THANKS FOR WATCHING” screen.
The central idea of the lecture is a consistent shortcut for dividing a number in a given ratio: sum the ratio terms to get the total number of parts, divide the original amount by that sum to find the value of one part, and then multiply each ratio term by this unit value to obtain individual shares. This method is first demonstrated with a simple two-way division (153 lakh in the ratio 4:5), where one part equals 17 lakh and the shares are 68 and 85 lakh. It is then extended to a three-way partnership division (Rs. 10,85,000 in the ratio 7:11:13), where one part equals Rs. 35,000 and Sunderlal’s share is Rs. 3,85,000. The most important conceptual extension involves chained ratios, where separate pairwise ratios must first be combined into a single multi-term ratio before applying the one-part method. In the Neha-Tony-Sonu example, N:T = 2:3 and T:S = 3:5 are combined into N:T:S = 2:3:5 because the common term Tony is already consistent (3 in both ratios). In the final four-person example, G:M = 1:2, M:J = 2:3, and J:K = 3:4 are combined into G:M:J:K = 1:2:3:4, again because the overlapping terms match. The verification step in the first example—adding the calculated shares back to the original total—is a useful habit that confirms correctness. The lecture uses story-based framing and character names to make the abstract ratio concept concrete, but the underlying arithmetic is identical across all examples: total parts → value of one part → individual shares.