← Near Enough · Lesson 3 of 4
Ten per cent and half again
Ten per cent is the easiest percentage there is: move the decimal point one place left. 10% of $46 is $4.60.
Fifteen per cent is ten per cent and half of it again. Half of $4.60 is $2.30, so 15% of $46 is $4.60 + $2.30.
Twenty per cent is ten per cent doubled. Most of the percentages you meet at a counter are built from these two moves.
What is 15% of a $46 bill?
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