If you double a number and then add 1616 , you get two fifths 2 5 of the original number. what is the original number?

Let the original number be x.

Acc. to the question,

2x+1616 = (2/5) x

or, 10x+8080=2x

or, 10x-2x = - 8080

or, 8x = - 8080

or, x = - 8080/8

or, x = - 1010

Therefore, the original number is - 1010