Question
Find the cube root of 614125 through estimation.

Answer

Given, number is 614125.
So, groups of 614125 are
Image
In the first group, the number 125 ends with 5.
We know that 5 comes at the unit place of a number only when its cube end in 5.
So, 5 will come at unit place.
Now, in the second group, the number is 614.
$\begin{array}{l}\because(8)^3=512 \text { and }(9)^3=729 \\ \text { and } 512<614<729\end{array}$
So, tens place of required cube root is 8.
Hence, $\sqrt[3]{614125}=85$

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