Relax

Respuesta :

To check whether or not it is correct, you would multiply 30 by 4. 
30 x 4 = 120

If you need to do it in smaller chunks, multiply 4 by 10
4 x 10 = 40
And then multiply the 40 by 3
40 x 3 = 120
elloitssky
Work it backwards... 30•4=120