Question 602441
Let x = the unknown number (ie the "given number")


40% of a given number is 8


<font color="red">40%</font><font color="blue"> of </font><font color="orange"> a given number </font><font color="green"> is </font><font color="purple"> 8</font>


<font color="red">0.4</font><font color="blue"> * </font><font color="orange"> x </font><font color="green"> = </font><font color="purple"> 8</font>


<font color="red">0.4</font><font color="orange"> x </font><font color="green"> = </font><font color="purple"> 8</font>


0.4x = 8


x = 8/0.4


x = 20


So the "given number" is <font color="red">20</font>


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Now take 15% of that given number:



20*0.15 = 3



So 15% of 20 is <font color="red">3</font>


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Answer: 


15% of the given number is <font color="red">3</font>