Multiply With Your Hands

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Being able to multiple with your fingers is a valuable skill to have, and people have been doing it since at least the 15th century. We may have cellphone calculators, but in many cases it is actually easier to keep your phone in your pocket and multiply with your fingers. It is also helpful for students learning multiplication for the first time. For finger multiplication to work successfully, you must first know your multiplication tables from one to five. Multiplying by hand works for the tables of six, seven, eight, nine and ten.

Steps

Multiplying by Nine

  1. Hold your hands out in front of you with your palms facing up. Each of your ten fingers represent a number. Moving from your left thumb to your right thumb, count out the numbers from one to ten.
  2. Point the finger you want to multiply by nine down towards your body. For example, if you want to solve (9x3) you will want to hold down your middle finger on your left hand. The middle finger represents the number three because, if you count your fingers from one to ten beginning with your left thumb, your middle finger is the third finger.
  3. Solve the problem by counting fingers to the left and right. First count the fingers to the left of your bent finger - in this case there should be two. Next count the fingers to the right of your bent finger - in this case there should be seven. The first digit of the answer is 2 and the second digit is 7. The answer is 27![1]
  4. Try this with other multiples of nine. How would you multiply 9 and 2 with your fingers? What about 9 and 7?

Multiplying by Six, Seven, Eight and Ten

  1. Hold your hands so that your palms are facing your body and your fingers are facing each other. Again each finger will represent a number. Your pinkies represent the number six, your ring fingers will represent the number seven, your middle fingers will represent the number eight, your index fingers represent nine, and your thumbs represent the number ten.[2]
  2. Touch the fingers that represent your multiplication problem together. For example, if you want to figure out the problem (7x6) you would touch your left ring finger with your right pinky. Your left fingers represent the number on the left of the problem, and your right fingers represent the numbers on the right of the problem. Again, remember that each finger represents a number and that in this case, your ring finger represents seven and your pinky represents six. Therefore, you need to touch these together to solve this math problem.
    • You may have to bend your wrist awkwardly to do this!
    • As another example, if you were trying to calculate 9x7 you would touch your left index finger with your right ring finger.
  3. Add the fingers that touch together as well as the fingers beneath them. The next step is to count the touching fingers as well as the fingers below them. These will represent the 10s. In this case you would count the ring finger on your left hand, the pinky on your left hand and the pinky on your right hand. Each finger that you count will count as 10. In this case, the total is 30.
  4. Multiply the remaining fingers. The next step is to add together the number of fingers on each hand, not including the fingers that are touching. First count the number of fingers on your left hand that are above the touching fingers - in this case there are 3. Next, count the number of fingers on your right hand above the touching fingers - in this case there are 4. 3x4 = 12.
  5. Add the two figures together to find your answer. In this case you will add 30 to 12 for a total of 42. The answer to 7x6 is 42!
  6. Multiply by 10s using the same technique. For example if you want to find the answer to 10x7, begin by touching your left thumb with your right ring finger. Count the number of fingers below the touching fingers, including the fingers that are touching. There should be a total of 7, which remember means 70. Next, count the number of fingers above the touching fingers on your right and left hand. There should be 0 on your left and 3 on your right. Now multiply 3x0 which is 0, and add 70 to 0 for you answer. The answer to 10x7 is 70!
  7. Try this with other multiples of six, seven, eight and ten. How would you multiply 8 and 8 with your fingers? What about 7 and 10?

Related Articles

Sources and Citations

  1. ↑ https://www.dccc.edu/sites/default/files/faculty/sid_kolpas/mathteacherfingers.pdf
  2. ↑ http://www.moebiusnoodles.com/2014/04/multiplication-a-parlor-finger-trick/
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