The per store donated 11 and 3/8 pounds of cat food... first you gotta make the denominators equal so 19 and 3/4 becomes 19 and 6/8 then you add the puppy and dog food together (19 6/8 +18 7/8= 38 5/8) then you take 50 and subtract the value you just got (50 - 38 5/8) and you get tour answer at 11 and 3/8 pounds
