MCQ
If $a,\;b,\;c,\;d,\;e,\;f$ are in $A.P.$, then the value of $e - c$ will be
- A$2(c - a)$
- B$2(f - d)$
- ✓$2(d - c)$
- D$d - c$
So $b - a = c - b = d - c = e - d = f - e = K$
Where $K$ is a common difference.
Now, $d - c = e - d$
$ \Rightarrow $$e + c = 2d$.
$e{\rm{-}}c + {\rm{2}}c = 2d $
$\Rightarrow e - c = 2(d - c)$.
Trick : Check by putting $a = 1,\;b = 2,\;c = 3,\;d = 4,\;e = 5$ and $f = 6$.
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