Let's get this math done. We have 520 and we're going to multiply it by 3. This is the same as taking 520 and adding it to itself 3 times.
Step 1: 0 + 520 = 520
Step 2: 520 + 520 = 1040
Step 3: 1040 + 520 = 1560

So, 520*3 = 1560