Surface areas and volumes notes + Q&A|Latest 2026/2027

Surface areas and volumes notes + Q&A|Latest
2026/2027


## 1. Basic Ideas



**Area** measures the space covered by a **2-dimensional shape**.

Unit: cm², m², mm², etc.



**Surface area** measures the total area of all the **outside
faces/surfaces of a 3-dimensional solid**.

Unit: cm², m², etc.



**Volume** measures the amount of space occupied by a **3-
dimensional solid**.

Unit: cm³, m³, etc.



---



## 2. Important 2D Area Formulas



### Rectangle



genui{"shapes_measurement_learning_block":
{"type_id":"RECTANGLE_AREA"}}



[

A=l\times w

,]



where:



* (l) = length

* (w) = width



### Square



genui{"shapes_measurement_learning_block":
{"type_id":"SQUARE_AREA"}}



[

A=s^2

]



where (s) = side length.



### Triangle



[

A=\frac12 bh

]



where:

, * (b) = base

* (h) = perpendicular height



### Parallelogram



[

A=bh

]



### Trapezium/Trapezoid



genui{"shapes_measurement_learning_block":
{"type_id":"TRAPEZOID_AREA"}}



[

A=\frac12(a+b)h

]



where (a) and (b) are the parallel sides.



### Circle



[

A=\pi r^2

]