Questions tagged [arithmetic-operations]

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5
votes
1answer
138 views

Is a clear distinction made between signs and operators?

This question about FOIL, comments and answers made me think about the two roles of $-$: as a sign and as an operator. This struck me because the title "Why in the FOIL Method the terms are taken ...
2
votes
3answers
193 views

Why in the FOIL Method the terms are taken with their signs?

That was the most boring title I could choose but in all honesty, it is what the question is. Here is a reminder of the FOIL method that is used for multiplying two binomials. For example, to multiply ...
2
votes
3answers
105 views

Teaching three-year-old subtraction using the number line

I am aware of questions such as this one. On the other hand, I still believe that teaching a bright three year old subtraction is possible. He counts from $0$ to $100$ and backwards from $10$ to $-10$,...
0
votes
1answer
147 views

Viewing arithmetical operations as processes-possibly wrong and detrimental to long term math performance of the students [duplicate]

I think that the standard practice in the first grades when addition (or other operation) is taught as a "process" may be not so good. I always wondered why so many children lose interest in math ...
5
votes
5answers
798 views

How to correct visualization of mathematical expressions?

This happens a lot when I try to explain the commutative property, mostly in elementary grade levels. I say 2 + 3 = ? and then the student usually replies with 5. Albeit they're not wrong, it's ...
16
votes
1answer
248 views

Has Benezet's teaching experiment ever been reproduced?

In the 1930's, Louis Bénézet, a superintendent of several schools in New Hampshire made the interesting experiment of teaching no formal arithmetic until grade 6: In the fall of 1929 I made up my ...
0
votes
1answer
109 views

How to present the order of factors and summands for the usual multiplication procedure

In the following multiplication example, $$\begin{align} 34\;& \\\underline{\times\;\; 7\;}& \end{align}$$ first one would multiply the units digits, producing the partial product $28$ as ...
5
votes
1answer
214 views

Subtraction using Addition (Austrian Method), is it useful to learn this method instead of the usual “borrow” method?

I came across this method to perform subtraction using addition and not using the "borrow" concept, apparently because it is harder to learn it that way. Video - https://www.youtube.com/watch?v=...
8
votes
5answers
441 views

Exponents with Negative Base; with or without Parentheses

How can I convincingly and mathematically explain the reason behind difference between $(-1)^2$ and $-1^2$? I used to add "negation" to the order of operations, in the same row as multiplication and ...
4
votes
6answers
298 views

How to teach multiplication between integers for the first time

Some teachers teach multiplication between integers with the following rules: plus with plus gives plus plus with minus gives minus etc. So for example in order to deal with the ...
4
votes
2answers
184 views

What's the word for addition and subtraction without borrowing or carrying over?

Is it regrouping? Upon googling it seems regrouping is borrowing or carrying over collectively. What's the word for not borrowing and carrying over? It's supposedly to train mental computation. ...
2
votes
1answer
64 views

How to use these actions words for subtraction?

Do the following sentences express 5-2? a. 5 fewer 2 is 3 b. 2 fewer than 5 is 3 c. 5 less 2 is 3 d. 5 gave 2 is 3 I also saw online that "shared" can also mean "...
9
votes
3answers
133 views

Learning operator priorities by drawing trees

As far as I know (and here I am refering to my own math education), operator priorities of $+$, $-$, $\cdot$, $\div$, power and paranthesis are taught via some simple phrases like "pointy" operators (...
8
votes
3answers
434 views

What is the pedagogical justification and history for using mnemonics to teach order of operations?

There was previously a question/rant here on MESE about why so many are still using the PEMDAS/BODMAS/BIDMAS/BEDMAS mnemonics to teach order of operations. The question was deleted (still viewable by ...
11
votes
3answers
371 views

Why is modulo not an elementary operation?

Like it is just as primitive as makes intuitive sense in a way similar to division. I feel like teaching 4th graders the modulo function would complement learning division extremely well, as it helps ...
11
votes
8answers
8k views

Proof of why BODMAS (or BIDMAS) works?

In my first full-time teaching post, it is very likely that I'll need to be teaching a small amount of GCSE Mathematics to students retaking it. One thing that has been bugging me is that I can't seem ...
7
votes
4answers
277 views

Teaching arithmetic operations ($+ - \times \div$) to a 3 year old

What is the best way to teach the standard arithmetic operations ($+ - \times \div$) to a 3 year old child? Also: How we do know if the child has really understood it? can a kid be 3 years old ...
23
votes
7answers
4k views

Repeated addition: standard notation?

My daughter showed me the picture below, which came from 9GAG. It shows a question on an exam asking the student to "use the repeated addition strategy to solve: 5 x 3." The student answered "5+5+5" ...
11
votes
1answer
654 views

Method for teaching factorization

A while back I stumbled on teacher's website that advocated a different way to teach factorization. Rather than jumping straight to factorization practice, the teacher first had their student's ...
11
votes
2answers
123 views

Visual questions for 6th graders

I'm tutoring a 6th grader in math at the moment and because she never has a ton of homework I like to give her some interesting extra problems to do. It seems she really enjoyed a problem I showed ...
16
votes
3answers
200 views

How do I help a 6-year-old understand the meaning of her sums

I am tutoring a Grade 2 girl in arithmetic. She has demonstrated an ability to add two-digit numbers with carrying. For example: $$\;\;14\\ +27\\ =41$$ I asked her to write this out horizontally, ...
4
votes
1answer
550 views

Parse out 2/3 of 30 minus 11

Note - I am not a math teacher; I am seeking an answer from a math teacher. While helping my son with his 5th grade homework today we had one answer wrong. I'm not sure I agree with the book and ...
7
votes
6answers
1k views

Is there any other procedure to find the square root?

If no calculator is allowed, and we want to find the square root of a square number if it is large and analyzing to prime factors is hard, how can one proceed? For example, what to do if the number ...
29
votes
16answers
8k views

Dividing by zero

I was having a discussion with a friend and fellow mathematics teacher the other day when the topic of dividing by zero came up. She is the department head and had this in a questionnaire she gave to ...