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Science,English,and math 4th

レス500 HIT数 3283 あ+ あ-

匿名さん
21/05/07 20:00(更新日時)

I will start from now on

(兄の英語スレをよろしく‼)


No.3244915 21/02/28 23:15(スレ作成日時)

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No.381 21/04/21 22:10
燻し銀三 ( 60代 ♂ IJ7P0b )

【Do you know an almighty pair of scales?】

《A question in which a sense of mathematics is necessary for us》

For example, when expressing 13 with the binary system, it's 1101, and it means that we measure something of which with each of single weight of 13 gram with a weight of 8 gram, 4 gram and 1 gram.

Though I can’t understand when 13 is expressed with the number of the binary system, 1101, why do we adopt those three kind of weigh? The total weight of the three kind is 13, I know why it is, but I’m not sure that the relation of the number which is expressed with the binary system and...

No.382 21/04/21 22:39
燻し銀三 ( 60代 ♂ IJ7P0b )

【Do you know an almighty pair of scales?】

《A question in which a sense of mathematic is necessary for us》

...but I’m not sure the relation between the number which is expressed with the binary system, 1101 and three kinds of weight, 1 gram, 4 gram and 8 gram.

The author continued, all the numbers in decimal system are expressed with those in the binary system, we have only to prepare for every weight of binary system one by one. It’s enough. Why?

To return to our main subject, I’ll start again.

But for example, how about in a case when we have to prepare for a weight of 4 to nth power?

No.383 21/04/25 08:19
燻し銀三 ( 60代 ♂ IJ7P0b )

【Do you know an almighty pair of scales?】

《A question in which a sense of mathematical is necessary for us》 

Then we think it of with quaternary in which number from 1 to 3 in every digit. When trying to express 13 with the quaternary, it’s 31. Why?

Its numerical equation is 3×4+1×0=13

When trying to express with English, 3 multiplied by four to the first power plus 1 multiplied by four to the 0th power, then three means three weight is used. Then 1 is 4 to the 0th power, it means a single weight is used. It’s 31, so 13 is equal to 31 when changing from the decimal system to quaternary.

No.384 21/04/25 08:46
燻し銀三 ( 60代 ♂ IJ7P0b )

【Do you know an almighty pair of scales?】

《A question in which a sense of mathematic is necessary for us》

In the same way when expressing 31 with the binary system, 8+4+1, it means that 1×2 to third power +1×2 to the second power+1×2 to 0th power. Three weight of 2 gram, two weight of the two grams, and a single weight of 1 gram is used. It’s 1101.

As to the binary system, if its digit is used, then putting 1, and if it’s not used, then putting 0.

The author continued his theory on the almighty pair of scales, but I don’t feel like expressing, for I find it boring. I’m sorry for it.

No.385 21/04/25 09:02
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing our both hands into an electronic calculator】

《There is few countries in which learning the multiplication table by heart》

We the Japanese learn the multiplication table in the second grade of elementary school. Learning the multiplication table may be the first deadlocked in arithmetic.

Everyone has memory of trying to learn it by heart with rhythmically, but a country where learning the multiplication table from 1 to 9 by force is few in the world.

For example, when learning it in the area of English speaking, a list of times table is used. The multiplication from...

No.386 21/04/25 09:19
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing both of our hand into an electric calculation】

《Few countries where leaning the multiplication tables by heart》

A list of multiplication table is used in the area of English spoken when learning the multiplication. There are multiplications to 12×12.

If going on using the list of the time table, they’ll learn it by heart automatically, and it’s all right, in America or Australia they’ve thought like that.

Why is it to 12×12?

1 feet is 12inch, and 1 dozen is 12, though it has been abolished, 1 shillings used to be 12pence in England, for the duodecimal system 12進法 is...

No.387 21/04/25 09:48
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing both of our hands into an electronic calculation】

《Few countries where learning the multiplication table by heart》

...for the duodecimal system is so frequently used in their everyday life that they have to adapt themselves to the duodecimal system.

《Japan where the electronic calculation has been forbidden》

Learning the multiplication table by heart has never been done by force in lots of foreign countries, for it may be related with the fact that they can use the electronic calculation at will in junior high school.

An questionnaire that whether or not they allow...

No.388 21/04/25 09:59
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing both of our hands into an electronic calculator】

《Few countries where learning the multiplication table by heart》

An questionnaire was done that whether they have allowed the students to use the electronic calculator in the class of math or arithmetic over some of foreign countries.

At the time of the fourth grade in elementary school, almost all of the countries, including Japan, have never allowed it, but the second grade in junior high school, the countries in which they allow to use the electronic calculation at will have increased so much.

After 10 years old...

No.389 21/04/25 10:17
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing both of our hands into an electronic calculator】

《Few countries where an electronic calculator has been prohibited》

After the age of 10 when cultivating an ability of logical thought, they want the children to spend on more time to think over something more logical rather than a simple work like the calculation.

On the contrary, teachers who allow the students to use the electronic calculator at will at the second grade in junior high school accounts for no more than 6% in Japan.

While the electronic calculator made in Japan has been used at school all over the world...

No.390 21/04/25 10:30
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing both of our hands into an electronic calculator】

《Japan where an electronic calculator has been prohibited》

...ironically the electronic calculation has hardly used in the class of Japan, but if the country where the electronic calculator is forbidden to use at will and learning the multiplication table by heart by force has higher mathematical ability, carrying out the education of Japanese style is significant, but unfortunately, there is none of the situation.

Hong Kong and Singapore where the electronic calculator has been used at will have higher mathematical ...

No.391 21/04/25 11:05
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing our both hands into an electronic calculator】

《Japan where the electronic calculation has been forbidden》

Hong Kong and Singapore where the electronic calculator has been used at will have higher mathematical ability in the questionnaire before. In addition there are lots of reports that if making the student use a tool for calculation like the electronic calculator or the list for multiplication table,it enhances their mathematical ability.

When trying to learn the multiplication table by heart, we Japan muttering rhythmically, but it seems to be strange for the....

No.392 21/04/25 11:22
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing both of our hands into an electronic calculator】

《Japan where the electronic calculator has been forbidden》

....but it seems to be odd for the Europeans and Americans who don’t have a habit of learning the multiplication table by heart. They thought we the Japanese looked as if we had muttered an incantation or something.

《Having a good command of the multiplication by counting on our fingers》

An expression on 九九 which is the multiplication table in Japan has been deep-rooted in Japanese life.

For example, 四六時中, 4×6=24, at the time of 24 hours a day, around the clock...

No.393 21/04/25 11:39
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing both of our hands into an electronic calculator】

《Having a good command of multiplication by counting on our fingers》

...18番 2×9=18, the one with expressed with the number of 2 and 9, it means that the one who we tend to hate, 29い奴, it has changed into an artistic skill on an actor who has popular among us.

28ソバ, 2×8=16, the price of a bowl of soba used to be 16文 in Japan in the past.

A culture of making the people learn the multiplication table by heart has existed in Japan, China, India, and other countries in Asia from long long ago, but except for the countries...

No.394 21/04/25 11:50
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing both of our hands into an electric calculation】

《Having a good command of multiplication by counting on our fingers》

...except for the countries how did they multiple, especially at the time when there was no electronic calculator, for they couldn’t carry the list of the multiplication table with them everywhere around the clock.

Without learning the multiplication table by heart, nor carrying the list of the multiplication table with them, a way of being able to do an easy multiplication was contrived around 15 century. It’s the multiplication by counting on fingers.

No.395 21/04/25 12:18
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing both of our hands into an electronic calculator】

《Having a good command of multiplication by counting numbers on fingers》

Without clenching our fist, opening our hands, bending from the thumb to the little finger one by one when calculating , and an order on 8×6 is shown in the book like the next.

1 Counting 8 on fingers in one hand and 6 is with other hand.

2Adding the number of bending fingers on both hands. 2+4=6

3Subtracting 6 from 10, and multiplying 10 by 4, 10−6=4, and 4×10=40

4 Multiplying each number of bending fingers, 4×2=8

5 Adding 40+8=48.

At last we...

No.396 21/04/25 12:36
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing both our hands into an electronic calculator】

《Having command of multiplication by counting numbers on fingers》

At last we reach the answer. If trying to express with letters, we may have felt roundabout so much, but doing it with our fingers actually several times, we’ll learn to find its answer more quickly, the author said like that.

To tell the truth, I’ve never heard of the way of calculation until now, so I’ve never tried it. The author continued.

It's limited to multiplications of which number is bigger than 5.

The people long long ago who didn’t learn the...

No.397 21/04/25 21:10
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing both of our hands into a electric calculator】

《Having command of multiplication by counting numbers on our fingers》

The people long long ago when they didn’t learn to understand the multiplication table, they thought of the multiplication by small number each other like 2×4, they regarded as addition of 2 four times, 2+2+2+2=8

But as to 8×6, when trying to think it of addition of 8 six times, they tend to get a little confused, so they contrived that way, the author said like that.

As to the multiplication table for 9, we can find its answer more easily.

No.398 21/04/25 21:31
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing both of our hands into an electronic calculator】

《Having command of multiplication by counting numbers on fingers》

I’m going to show the way on 9×3.

1 We spread out our both palms and direct them toward ourselves.

2 As it 9×3, we bend the middle finger alone in the left hand.

3 The left side of the two fingers from the bending middle finger is the second digit, so it’s two. The other fingers from the bending middle fingers are the first digit, so it’s 7, so it’s answer is 27.

Though it’s answer is correct, to my sorrow,I don’t understand why it is. I find it strange.

No.399 21/04/25 21:51
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing both of our hands into an electronic calculator】

《What should we do so as to decrease the people who are poor at math?》

Needless to say its remarks aren’t from me but from the author who teaches math, and he said like the next.

If making students calculate a multiplication of both three digits, or dividing some number on fourth digit by other number on two digit by writing, he doesn’t think it’s so significant, from the situation in which he teaches math for students in junior high school or high school or grown ups.

If the students solved questions in which that kind...

No.400 21/04/25 22:04
燻し銀三 ( 60代 ♂ IJ7P0b )

【A way of changing both of our hands into an electronic calculator】

《What should we do in order to decrease the people who think they are poor at math?》

When students solved the question in which that kind of calculations were included, he made it rule to tell them to use the electronic calculator, or saying the way of thinking is all right with it, so go ahead from that, for he wanted students to spend their time on solving other problem rather than the calculation.

But students who are good at an applied question in which they need an ability of thinking have an ability of calculation...

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