Let n be a positive integer. By removing the last three digits of n, one gets the cube
root of n. Find a possible value of n.
The first thing to do is narrow it down by finding the numbers that become 3 digits shorter when their cube root is found.
The cube roots of 10000 and 99999 are about 21.5 and 46.4
This narrows it down nicely as the cube root must be from 22 to 46 and near the middle.
30^3 = 27000
is just a little too small
31^3 = 29791
still to small
32^3 = 32768 <----- got it
33^3 = 35937
which is too big.
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Posted by Jer
on 2014-02-11 10:43:09 |