Question

rahil has a certain number of chocolates he gave one third of the chocolate to his brother one- sixth of it was  given to his friend he was then left with 30 chocolate how many chocolate did he gave to each one

Answer 1

Let the total number of chocolates with Rahil be $x$.
No. of chocolates given to brother = $x/3$
No. of chocolates given to friend = $x/6$
No. of chocolates remaining with Rahil = $30$
$x = x/3 + x/6 + 30$
⇒ - 30 = x/3 + x/6 - x (Transposing 30 to LHS, becomes - 30 and transposing x to RHS, becomes - x)
⇒30 = - x/3 - x/6 + x
⇒30 = - 2x/6 - x/6 + 6x/6
⇒30 = 3x/6
⇒3x = 6 * 30
⇒3x = 180
⇒x = 180/3
⇒x = 60
Total no. of chocolates with Rahil = $60$
No. of chocolates given to brother = $x/3 = 60/3 = 20$
No. of chocolates given to freind = $x/6 = 60/6 = 10$

Answer 2

Total no. of chocolates with Rahil = x.
Chocolates given to brother = x/3
Chocolates given to friend = x/6.
Chocolates left  = 30
30 = - x/3 - x/6 + x 
30 = (- 2x- x + 6x) / 6 
30 = 3x / 6 
3x = 6 * 30 
3x = 180 
x = 60 
chocolates = 60
chocolates given to brother = 20
chocolates given to frened = 10