- Confusing the formula for C and A (C requires Diameter; whereas A needs the square of the radius) ;
- Mistook radius for diameter or vice versa;
- Using the wrong value of pi for the wrong accasion;
- Missing units in the final answer
- Using the wrong units for the answer (m, cm, m2, cm2):
- "m" instead of "cm" or vice versa
- Using square unit (cm2) in place of a length unit (cm) for perimeter or vice versa for area.
Q(e) --> Missing out the 2 R
--> 56.55 ?? (actual: 56.54866776)
--> pi x 9 is "pi x R" ???!!! , But C = pi. D
Pg 34 (problem with rounding off?)
Q3(b) 5538.96 ~ 5539.0 , Many with 5538.1 ???