Answer:
scale factor 3 is the answer.
Explanation:
Length = 18 in
Breadth = 3 in
height = 10 in
Volume of cuboid = l × b × h
V = 18 × 3 × 10
V = 540 in³
540 in³ is the original volume. The volume needs to be tripled, so multiply the original volume with 3
V = 540 × 3 = 1620 in³
∴ 1620 in³ will be the new volume if it's tripled and the scale factor is 3.