Sure thing! We've got 320 and we're gonna multiply it by 4. That's the same as adding 320 to itself 4 times.
Step 1: 0 + 320 = 320
Step 2: 320 + 320 = 640
Step 3: 640 + 320 = 960
Step 4: 960 + 320 = 1280

So, 320*4 = 1280