Algebra practice question

Answer: 8

d + c = 26 and 2d + 4c = 68. Substituting d = 26 − c: 52 − 2c + 4c = 68 → 2c = 16 → c = 8.

Common wrong answers

If you answered 13

13 assumes equal numbers.

If you answered 17

17 is 68 ÷ 4, as if every animal were a cow.

If you answered 18

18 is the number of ducks.

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