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How to calculate the age of a person using palmistry 
Choose the correct hand. 
Often times, a palm reader will rely on both hands to give a more accurate reading. However, some palmists prefer to use one primary hand, and which hand is chosen will depend on both the age and gender of the person being read.
Men who are under the age of 30 should offer the left palm as the primary hand. Men over 30 years of age should use the right palm as the primary hand.