Is 30ml greater than 30cm

The measures as given cannot be compared:

ml

(millilitres) are a measure of volume

; whereas
cm

(centimetres) are a measure of length

.


However, cubic

centimetres

(cu cm or cm^3 or cm3) are

a measure of volume:

1 ml = 1 cu cm (= 1 cm3)
→ 30 ml = 30 cu cm
so 30 ml is not greater than 30 cu cm (they are equal).