Question

Write the ones digit of the cube of the number ending in 7.
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Answer 1

Answer:

We know that,

The cube of number having 1,4,5,6 or 9 in unit place will end in 1,4,5,6 or 9

And, if the numbers have:

2 in unit place, then it’s cube ends in 8

8 in unit place, then it’s cube ends in 2

3 in unit place then it’s cube ends in 7

7 in unit place then it’s cube ends in 3

0 in unit place then it’s cube ends in 0.

So now,

Unit digit of number 725 is 5, hence its cube will end in 5.