If I sell four-fifth of 10 apples, how many are left?
2
Four-fifths of 10=45×10
=4×105
=8 apples
So, four-fifths of 10 apples is 8 apples,
i.e., 8 apples were sold
Therefore,
Apples left = Total number of apples - Number of apples sold
= 10 - 8 = 2 apples