Q155
ArithmeticNumber Series & Progressions
The $6^{th}$ term in the following series is $ab^2+bc^2+cd^2+de^2+\ldots$
- a.$ef^2$
- b.$fe^2$
- c.$fg^2$
- d.$g^2f$
Answer: (C) $fg^2$
Each term uses two consecutive letters, term $n$ pairing the $n^{th}$ and $(n+1)^{th}$ letters as (letter)(next letter)$^2$: term 5 is $ef^2$, so term 6, using $f$ and $g$, is $fg^2$.