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Retired teacher explains how to show the child the multiplication table
How to teach a child to count in the mind? The task, to confess, is very difficult. Especially when the student is not given a multiplication table. “Here you can’t explain logically, we make you crank,” the parents complain.
Meanwhile, there are tricks that will turn monotonous rote learning into an exciting game. For example, the multiplication table by 9 can be easily mastered literally on your fingers.
How to teach a child to count in mind A simple way to multiply by 9 Put your hands in front of you with your palms down. Imagine that each finger from left to right corresponds to its serial number. Then the little finger of the left hand will be a unit. The index finger of the same hand will be a four, and the index finger of the right hand will be a seven.
Let's say you want to multiply 9 by 7. To do this in our system is simple. You just need to bend your seventh finger. Now count your fingers to the left of the bent. That would be dozens, and in our case there would be six.
Count your fingers to the right of the bent. There are three of them in the photo and they will be one. So we have six dozen and three units, which is 63. But maybe it's a coincidence? Check it out.
Let's try multiplying 9 by 5. Bending the thumb of the left hand (its serial number 5). Counting fingers: left 4, right 5. There were four dozen and five units, or 45. As expected, life hacking works!
To better remember the multiplication table by 9, you will need another funny pattern. As you have noticed, the numbers in the first column increase each time, and in the second column decrease by 1.
Multiplication of numbers consisting of units by themselves How to simply multiply numbers with the same number of units? Take this table into service, it will be easier to solve such examples with it. For example, 1111 x 1111 = 1234.321. This result should be looked at more closely. See the pattern?
The number consists of two mirror halves, and the symmetry point in it corresponds to the number of units. Knowing this, 111111111 by 111111111 can be easily multiplied without a calculator and counting into a column. Just write the numbers from 1 to 9 and then the same sequence in reverse order.
Dividing large numbers by 5 is very simple. You just need to multiply the number by 2 and move the comma. For example: 235/5. Multiply 235 by 2 (235 x 2 = 470). Transfer the comma to the left: 47.0 or just 47.
Squaring numbers ending in 5 This technique will help to quickly square a two-digit number that ends in 5. All you have to do is multiply the first digit of a number by the number that is one more and put 25 at the end.
191183
For example: 85 squared (85 x 85). Step 1. Multiply the first digit by the first digit increased by one: 8 (8 + 1) = 72. Step 2. Add to 25: it turns out 7225.
Agree that mathematics is not only interesting, but also very beautiful! And to master it better help fascinating books that we offer to our readers.
Meanwhile, there are tricks that will turn monotonous rote learning into an exciting game. For example, the multiplication table by 9 can be easily mastered literally on your fingers.
How to teach a child to count in mind A simple way to multiply by 9 Put your hands in front of you with your palms down. Imagine that each finger from left to right corresponds to its serial number. Then the little finger of the left hand will be a unit. The index finger of the same hand will be a four, and the index finger of the right hand will be a seven.
Let's say you want to multiply 9 by 7. To do this in our system is simple. You just need to bend your seventh finger. Now count your fingers to the left of the bent. That would be dozens, and in our case there would be six.
Count your fingers to the right of the bent. There are three of them in the photo and they will be one. So we have six dozen and three units, which is 63. But maybe it's a coincidence? Check it out.
Let's try multiplying 9 by 5. Bending the thumb of the left hand (its serial number 5). Counting fingers: left 4, right 5. There were four dozen and five units, or 45. As expected, life hacking works!
To better remember the multiplication table by 9, you will need another funny pattern. As you have noticed, the numbers in the first column increase each time, and in the second column decrease by 1.
Multiplication of numbers consisting of units by themselves How to simply multiply numbers with the same number of units? Take this table into service, it will be easier to solve such examples with it. For example, 1111 x 1111 = 1234.321. This result should be looked at more closely. See the pattern?
The number consists of two mirror halves, and the symmetry point in it corresponds to the number of units. Knowing this, 111111111 by 111111111 can be easily multiplied without a calculator and counting into a column. Just write the numbers from 1 to 9 and then the same sequence in reverse order.
Dividing large numbers by 5 is very simple. You just need to multiply the number by 2 and move the comma. For example: 235/5. Multiply 235 by 2 (235 x 2 = 470). Transfer the comma to the left: 47.0 or just 47.
Squaring numbers ending in 5 This technique will help to quickly square a two-digit number that ends in 5. All you have to do is multiply the first digit of a number by the number that is one more and put 25 at the end.
191183
For example: 85 squared (85 x 85). Step 1. Multiply the first digit by the first digit increased by one: 8 (8 + 1) = 72. Step 2. Add to 25: it turns out 7225.
Agree that mathematics is not only interesting, but also very beautiful! And to master it better help fascinating books that we offer to our readers.
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