Lessons · Quantitative Reasoning
CLT Quantitative Reasoning · Lesson
Area and volume
Know the area of rectangles, triangles (½bh) and circles, and the volume of boxes (lwh) and cylinders (πr²h). Scaling a length by k scales area by k² and volume by k³.
- Draw or label the figure with every measurement given.
- Choose the formula and substitute carefully, keeping units the same.
- For "what happens if" questions, use the scale rule instead of recomputing.
Q. A cylinder has radius 3 and height 4. What is its volume?
Answer 36π
πr²h = π × 9 × 4 = 36π.
- Doubling the radius and expecting the area to double. It quadruples.
- Using the slanted side of a triangle as its height. The height is perpendicular to the base.
Every practice question comes with a full explanation, including why each wrong choice is wrong. Free, with no account.