OK, let's work through this together. We're starting with 407 and we're going to multiply it by 7, which means we add 407 to itself 7 times.
Step 1: 0 + 407 = 407
Step 2: 407 + 407 = 814
Step 3: 814 + 407 = 1221
Step 4: 1221 + 407 = 1628
Step 5: 1628 + 407 = 2035
Step 6: 2035 + 407 = 2442
Step 7: 2442 + 407 = 2849

So, 407*7 = 2849