Answer:
length = 15 cm
Step-by-step explanation:
The volume of the box = length * width * height
Given: volume = 450 cm³ , width = 10 cm and height = 3 cm
∴ 450 = length * 10 * 3
∴ 450 = 30 * length
∴ length = 450/30 = 15 cm
so, the box will be 15 cm long.
