Question

Find the cube root $64$ by successive subtraction of numbers:

$(1,7,19,37,61,91,127,169,217,271,331,397,...)$

• A. $6$
• B. $12$
• C. $8$
• D. $4$

Answer 1

Answer: (D)

$4$

By consecutive subtraction of numbers $1,7,19,37,61,91,127,...$ from $64$, we get,

$64-1=63,63-7=56,56-19=37,37-37=0.$
That is, we obtain the difference is $0$ after $4$ successive subtractions.
$\therefore$ The cube root of $64=4$.

Hence, option $D$ is correct.