Hi everyone, can anyone tell me why the answer for the last question was not E? I got 19 and I think in the video they missed 5*5 and 7*7… if these don’t apply can anyone explain why, since they both have 4 factors as well? Thank you!

Missed 5 times 5 (25) and 7 times 7 (49) not 55 and 77 the numbers.

factor of 25 → 1,5,25 hence , three factors

factor of 49 → 1,7,49 hence, three factors