I was reading a book on ancient mathematics problems from Indian mathematicians. Here I wish to share one problem from Bhaskaracharya‘s famous creation Lilavati.

### Problem

A beautiful maiden , with beaming eyes, asks of which is the number that multiplied by 3 , then increased by three-fourths of the product, divided by 7, diminished by one-third of the quotient, multiplied by itself, diminished by 52, the square root found, addition of 8, division by 10 gives the number 2 ?

Ahh.. Isn’t it very long sentenced problem? The solution is here:
The method of working out this problem is to reverse the whole process — Multiplying 2 by 10 (20), deducting 8 (12), squaring (144), adding 52 (196), ‘multiplied by itself’ means that 196 was found by multiplying 14 to itself.
Now, Let the number be n.

Then applying initial part of the problem on it.
$$\dfrac {3n+3n \times \dfrac{3} {4} } {7} – \dfrac {1} {3} \times \dfrac {3n+3n \times \dfrac{3} {4} } {7} = 14$$
Now as we have:
$$\dfrac {n} {2} = 14$$
Thus the number is 28 .

Feel free to ask questions, send feedback and even point out mistakes. Great conversations start with just a single word. How to write better comments?
1. i was searching for the answer and i got it here. Thank you:)

2. Loki gubbi says:

Waw, this is an interesting problem with beautiful soln. What a knok from bhaskara! I realy hats of u . What a great indian! Thanks

3. prateek says:

what a problem it is?

4. Srinath kesav says:

5. ajay gole says:

fantastic try to give more examples please from indian ancient maths

1. sanjya says:

not good

1. asmi says:

hi can u pls solve the equation step by step
thank u
🙂

6. jayaprakash says:

I want learn lelawathi ganith

7. Kaushik says:

Its a very good question but i didn’t understand how u got the answer? The first half is clear but didn’t understand the second part which is $$dfrac {3n+3n times dfrac{3} {4} } {7} – dfrac {1} {3} times dfrac {3n+3n times dfrac{3} {4} } {7} = 14$$
Now as we have:
$$dfrac {n} {2} = 14$$
Thus the number is 28 .

8. Kaushik says:

Its a very good question but i didn’t understand how u got the answer? The first half is clear but didn’t understand the second half. If u can please show it in a better way. .

9. sumisha says:

What a nice problem?

10. ranjith says:

Nice solution

11. Vikas Ghode says:

The long expression you posted in above post is called First Expression(FE). I got another first expression which cannot be solved using fast tricks. But one you got can be solved easily(by assuming (3n+3n X (3/4))/ 7 to be another variable y) then I gets y-1/3y = 14
Solving it you will get y = 21
Put that y in FE original FE then you will get 28

12. Vishnu says:

Mera Bharath Mahaan…….

13. asmi says:

hi can u pls solve the equation step by step
thank u
🙂

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