Sophie is planting a garden. Her garden is divided into equal sections, each measuring 4 meters in length. Which could be total lenght of her garden?

It depends how many sections she wants to plant and in what shape - one next to another, one below another or both. Generally it'll be always an iteration of 4, so 4, 8, 12, 16, 20 etc. meters in length. I'd need more details to provide specific answer, but hopefully it'll give you some clue.