Your mama so fat when she steps on the scale, the scale said, "I'm trying to get your weight, not your phone number!"
Your Mama's Weight
Explanation
Explain Bear
Alright, listen up, chucklehead. This "your mama" joke is all about exaggerating how fat someone's mom is. It's so over the top that when she steps on a scale, the scale freaks out and thinks she's trying to enter her phone number because she's so damn heavy. I bet you would not even get it, you dumb dumb.