Crafty grandma Edith set her family down during Thanksgiving and told them they couldn't have any pet can pass until they worked out this puzzle are six-year-old granddaughter was the first to solve it can you work out what 9183 equals
8809=6 3590=2
7111=0 6855=3
9881=5 1012=1
6660=4 5731=0
5531=0 9191=2
2516=1 9193=?