Multiply any number by 15

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Trick:

15 × Number = (Number + Half of Number) × 10

Example: 15 × 822

1. 
   

   Half of 822 = 411

   
   


2. 
   

   Add: 822 + 411 = 1233

   
   


3. 
   

   Add a zero at the end = 12330

   
   

Final Answer:

15 × 822 = 12,330

Just add half and put a zero.