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ITMC 2018 Grade 9 National Preliminary set01 Question 5

ITMC · ITMC 2018 Grade 9 National Preliminary set01

Question 5

A rectangular box has length $a$, width $b$ and height $c$. Which expression equals its outside surface area?
  1. $a^2+b^2+c^2$
  2. $ab+bc+ca$
  3. $(a+b+c)^2$
  4. $(a+b+c)^2-(a^2+b^2+c^2)$
  5. None of these.