human
John buys 10 packs of magic cards. Each pack has 20 cards and 1/4 of those cards are uncommon. How many uncommon cards did he get?
assistant
How many uncommons are in each pack? ** Each pack has 20/4 = <<20/4=5>>5 uncommons
How many uncommons did John get? ** So he got 10*5 = <<10*5=50>>50 uncommons
#### 50