How many ways of method of putting two oranges and two apples on three plates of white, green and blue are there?
Noted that there shall be no empty plate.
Answer
12 ways
Solution
O=Orange, A=Apple
Pattern ① (OO, A, A) = 3 ways
Pattern② (AA, O, O) = 3 ways
PAttern③ (OA, O, A) = 3 × 2 × 1 = 6 ways
In total, 3 + 3 + 6 = 12 ways
