Question

two-third of number is less than the original number by 20.find the original number

Answer 1

according to question 1/3 is 20.therefore whole quantity will be 20×4=60

Answer 2

Hey there!

Let the original number be x.
According to the problem, 

As two-third of the number is less than the original number, the equation would be as below:

x -  1/3x  =   20
3x -  x/3  = 20  (after taking LCM of the denominators)
2x/3        = 20   
after multiplication, 
you get the original number is 30

..hope this helps :)