$(3 + 2 + 1) \times (6 +2 +1) = 54$ 
All the animals stand in rows in the magic forest. There is the same number of animals in each row. There are $3$ rows on the left of monkey and $2$ rows on the right of it. In its row, there are $6$ animals in front of it and $2$ animals behind it. How many animals are there in the forest? 
[1] $$36$$ 
[2] $$40$$ 
[3] $$45$$ 
[4] $$54$$ 
[5] $$63$$ 