Uncle Edgar has 500 chickens, ducks and gooses on his farm. 30% of the animals are gooses. If Uncle Edgar has 50 more chickens than ducks, how many ducks does he have?

ducks

The number of gooses: 500 × 30% = 150

The sum of chickens and ducks: 500 – 150 = 350

The difference between chickens and ducks: 50

Use the formula: Smallest number = (sum – difference) ÷ number of numerals

Thus,

The number of ducks: (350 – 50) ÷ 2 = 150