Question 99671
  

   Let :

     THE NUMBER = N

    SO, TWICE OF THE NUMBER = N+N= 2N
   
 SO, TWICE THE NUMBER INCREASED BY 4 = 2N +4

    SO, 2N +4 = 12

     SO, 2N = 12-4

   SO, 2N = 8

   SO, N= 8/2
      N = 4

CHECK :

  2N + 4
 = (2*4) +4
 = 8 + 4
 = 12