Question

Find the cube root of 389017 by estimation method

please answer fast along with steps​

Answer 1

Answer:

NOTICE

A.B.C.SCHOOL

FOUND!FOUND!

I AM SHIVANI OF CLASS 10 B THIS IS TO IS TO INFORM THAT I FOUND A WATCH IN THE PLAYGROUND NEAR A TAMARIND TREE. IT'S OF PINK COLOUR AND IT'S A GIRL WEARING WATCH. I AM HANDING IT OVER TO OUR P.T.SIR WHO EVER IS THE OWNER MAY COLLECT IT FROM SIR.

BY

SHIVANI

CLASS 10 B

Answer 2

Answer:

Step-by-step explanation:

Okay, divide the number in groups of three digits right to left: 389 and 017. There are two groups, so the answer (or its integer part) is two digits.

First group is  343≤389<512 , so the first digit in the answer is 7.

Conjecture: it is a perfect cube. If it is a perfect cube the rightmost digit in the answer shall be 3 (so its cube ends 7) So let's check if 73 is the answer.

73×73=4900+420+9=5329 .

5329×70=350000+21000+1400+630=373030 .

5329×3=15000+900+60+27=15987 .

And those two numbers do add up to  389017  .

So that is the answer