Question

one number is twice the other.when the larger number is subtracted from 50 the result is two more than the smaller umber subtracted from 40.find the numbers

Answer 1

A number is twice another number. 
one number x
other 2x 
when the larger is subtracted from 50,

So its 50-2x........(1)

the result is two more than when the smaller number is subtracted from 40. find the numbers 

(40-x)+2.............(2)

Hence equating (1) &(2)

50-2x = 40-x +2 
x = 8 
One number is X=8,
other number is 2X= 2×8=16.

Answer 2

Let the numbers be x and y.
So, 50-2x=2+40-x
50-2x=42-x
50-42=-x+2x
8=x