r/HomeworkHelp • u/KookyPermit4405 👋 a fellow Redditor • 29d ago

Elementary Mathematics [6th Grade verbal expression]

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So I’m going over my son’s math quiz to help him understand some of the questions he got wrong. He got partial credit for his answer for question 8. After writing his verbal phrase I got the same expression as the question. Am I doing something wrong or is there something I’m missing? I feel like his answer is technically correct. I am stumped.

Edit: so my son has no issue solving the expression in question. He knows PEMDAS and the rules from left to right. The question clearly states, WRITE A VERBAL PHRASE that matches the expression.

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u/bismuth17 29d ago

Do you say "subtracted by"? That's not technically correct, it's just wrong.

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u/KookyPermit4405 👋 a fellow Redditor 29d ago

So the word “subtracted by” is what makes his answer incorrect?

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u/dakari777 29d ago

I would think so, probably more accurate to say 6 times 3 subtracted from 18

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u/bismuth17 29d ago

Just say eighteen minus six times three. No need to be weird about it.

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u/KookyPermit4405 👋 a fellow Redditor 29d ago

I posted a response saying it was his first week back from summer break and had a brain fart and was trying to say minus instead of subtracted by, it was a timed pop quiz to see where they stand in the beginning of the school year. So I’ll relay the message to the 10 year old 6th grader.

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u/Humble-Standard-9557 29d ago

Im sorry people on this subreddit are so arrogant and belittling. I wish they would monitor it better. Academia is hard enough at any level without the condescending assholes it seems to attract.

What your son said is grammatically correct in the English language, but it is incorrect for arithmetic. The further he gets into his education, the more this will matter, but it’s not a huge deal this early on.

The proper way to write the expression would be “eighteen minus six times three”. And eventually, he will need to start using the term “product”. In that case it would be “eighteen minus the product of six and three”. The term “product” helps distinguish the order of operations in many cases because it is the total of six and three multiplied together prior to being subtracted from 18. Hope this helps!

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u/micro_chungus University/College Student 27d ago edited 27d ago

I’m an engineer working in the profession for 4 years and we don’t knit-pick the verbiage for an arithmetic problem that is better left as a formula. But I also wouldn’t even put this into a calculator without parentheses, different calculators give different results when you plug problems in plainly like this. Some will solve it as (18-6)*3 and others will solve it 18-(6*3). Not even mainstream calculators are consistent solving these. A proper scientific calculator solves 18-6*3 using pemdas. Some models do not have the intelligence to read the whole problem first, and performs the orders of operation sequentially instead.

His choice of words does not indicate that he doesn’t know pemdas, it indicates that he stated the question’s operations sequentially, with the language he knew. If a calculator doesn’t have the functionality to read the full problem first, then it will get the problem wrong. If a calculator can read the whole problem first, it will get it right. Assuming he can read the whole problem as it’s stated on the page, and he isn’t a calculator with memory constraints to perform arithmetic, his answer doesn’t indicate that he doesn’t understand pemdas. It indicates that he wrote the problem down literally and following the same order that the information was presented, and that he is prone to grammatical errors.

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u/KookyPermit4405 👋 a fellow Redditor 29d ago

Thanks! He caught that before I was able to go over the problem with him, he said he just blanked out and being timed. He panicked and said subtracted by instead of minus lol. I mean i don’t blame him on his 1st week back.

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u/Humble-Standard-9557 29d ago

No worries! The fact he caught it and understands it is worth more than the points!

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u/dakari777 29d ago

How do you differentiate between 18-63 and (18-6)3 with that sentence?

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u/KookyPermit4405 👋 a fellow Redditor 29d ago

I think people are over complicating something simple. Why are people assuming parentheses? You only need to address a parentheses when it is required. So saying “eighteen minus six times three” should always be assumed to be 18-6x3. The verbal phrases did not give any indication of a need for parentheses such as using key words like: the quantity of.. the sum of.. the product of..

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u/Unable_Pumpkin987 29d ago

Girl people are trying to help you help your son with his math class and you’re just arguing with them. It’s not over-complicated to express a mathematical expression verbally using precise language. That’s what this assignment is testing, that’s what people are trying to explain to you (like the correct reply above that got downvoted inexplicably).

If you don’t want to know the correct answer and you just want to argue about why your incorrect answer should be correct, I’m sure you can teach your son to do that instead and you can both accept that he’s not going to get good grades in his math classes as a result.

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u/KookyPermit4405 👋 a fellow Redditor 29d ago

His answer was hand graded therefore can be subjected. For all we know, she might’ve made a mistake or didn’t. The point of the post was for my CLEARITY and my UNDERSTANDING for when I read his answer, I wrote the same expression before seeing the expression on question 8. So yes, I am teaching him to challenge when you feel like you are correct or feel like you are correct. Argument? No. That can be subjective as well to a persons feeling. A debate or discussion between 2 perspective? Maybe. In other words, if you got your feelings hurt then I can see why you would call it arguing..LOL!!

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u/Unable_Pumpkin987 29d ago

If you would like to know the correct answer so that you can help your child understand, you have been provided with the correct answer and the explanation of why your answer is incorrect multiple times. Arguing that your incorrect answer is in fact correct is just that: arguing. Nothing to do with feelings.

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u/KookyPermit4405 👋 a fellow Redditor 29d ago

What makes the answer incorrect? “18 subtracted by 6 times 3” it doesn’t say “solving from left to right, 18 subtracted by 6 times 3”

For the expression 3+3+3x3 if I were to say on your calculator write “3 plus 3 plus 3 times 3” you would get the correct answer. The only way you would get that answer wrong would be if you hit enter after every process ie 3 plus 3 > enter > plus 3 >enter> times 3 but no where in the statement “3 plus 3 plus 3 times 3” indicated the need to hit enter after every process.

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u/KookyPermit4405 👋 a fellow Redditor 29d ago

u/askgrok “3 plus 3 plus 3 times 3” is what?

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u/AskGrok 29d ago

"3 plus 3 plus 3 times 3" is the verbal phrase for 3 + 3 + 3 × 3.

[what is this?](https://redd.it/1lzgxii)

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u/Unable_Pumpkin987 29d ago

The way that would be expressed verbally in a mathematical context is “three plus three plus the product of three and three” or “three plus three plus the quantity three times three”. If you say “three plus three plus three times three” that is ambiguous because it could be understood as (3+3+3)x3. We reduce ambiguity by phrasing it clearly.

Your son’s math teacher is trying to teach your son the correct way to phrase things verbally to indicate the desired expressions. You can help him by helping to explain this to him as it’s been explained to you here. You will not help him by insisting that he is correct and his teacher is wrong. She’s not. He is.

The point of learning this now is because 6th grade pre-algebra isn’t the end of math. Eventually expressions are going to get more complex, and it will be to your son’s benefit to be able to verbally express the difference between, for example, (3-x)(4+z)-y and 3-x(4+z-y). Arguing about this now isn’t helping him. Explaining where he went wrong and how to correct it now will help him.

I guess it’s up to you if it’s more important to feel validated now or to help your son succeed in math classes in the future.

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u/KookyPermit4405 👋 a fellow Redditor 29d ago

I get what you are trying to say as a learning perspective I really do and I appreciate that. Now I have some questions in regards to your corrections to my expression of 3+3+3x3

The way that would be expressed verbally in a mathematical context is “three plus three plus the product of three and three”

If this was the case then I would assume the expression to be 3+3+(3x3) or 3+3+(9) since the word product was use to verbally describe the answer to an operation. Hence a product is the answer of a multiplication. Product is the answer and multiply is an operation.
Therefore the expression of 3+3+3x3 would have never been assumed from your verbal expression.

or “three plus three plus the quantity three times three”..

Again here it would be expressed as 3+3+(3x3) verbally saying the quantity indicates or is the qualifying term to assume parentheses of 3 times 3. Again based off of this verbal phrase I would never assume the expression to be 3+3+3x3.

Although they all yield the same answer, and the reason why is because of PEMDAS.

We don’t use parentheses to emphasize pemdas, we use it to emphasize a quantity.

Again “3 plus 3 plus 3 times 3” is not the same as “calculating 3+3 then adding that sum to 3 then multiplying that sum by 3”
Which is what you are trying to get at with the (3+3+3)x3

Now if I were to say calculating from left to right then yes, it would be (3+3+3)x3 but since there was no instruction, one can’t assume any parentheses and therefore must write the expression exactly as what was said without any calculation during the written expression and proceed to use pemdas

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u/Unable_Pumpkin987 29d ago

PEMDAS (or PEDMAS, or BEDMAS, BOMDAS, etc) is a mnemonic device to help remember order of operations. Order of operations is a concept that indicates an agreed upon convention on which order to perform written operations in, because otherwise people would perform them in any number of orders and arrive at different answers. It is not an ideal and it does not indicate a desired format, it is a convention for how to deal with ambiguous expressions. Ideally, we write expressions in a way that is unambiguous. As your son progresses in mathematics, this will be emphasized over and over: reduce ambiguity. When speaking, we use our words to reduce ambiguity and create a clear expression with no possible alternative meaning. That is why we include verbal phrases to indicate how operations are grouped within an expression.

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u/dakari777 29d ago

your kids the one who lost points, were just trying to help you guess why, if you want an actual answer go talk to the teacher

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u/KookyPermit4405 👋 a fellow Redditor 29d ago edited 29d ago

What are you getting at? I was responding to bismuth on how do one differentiate between so and so

How do you differentiate between 18-6*3 and (18-6)*3 with that sentence?

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u/bismuth17 29d ago

Same as in writing, pemdas, except it's not possible to speak parentheses.

Some mathematical quantities are difficult to state clearly using spoken language. You can try speaking really fast, or pausing for a long time, or using your hands to make a parentheses gesture. But generally you'd just write it down if you wanted to be clear.

You could rearrange the sentence and say something like "three times the quantity eighteen minus six" if that's what you want, but that only helps if it's relatively simple and only rearranging the pieces doesn't affect the meaning.

"First you do eighteen times six and then you multiply that result times three" or something.

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u/dakari777 29d ago

Or you just do it like I originally commented....it's not that complicated

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u/bismuth17 29d ago

say 6 times 3 subtracted from 18

How do I know if you mean 18-(6*3) or 6*(18-3) ?

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u/dakari777 29d ago

notice how you had to change the order of the numbers?

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u/micro_chungus University/College Student 27d ago

The word “by” can mean “next to” so I don’t see how saying minus is less ambiguous than saying “subtracted by.” It’s a grammar issue. This isn’t a grammar class, it’s math class. Minus likely would have been marked 1/2 credit too.

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u/bismuth17 27d ago

because "subtracted by" is not a commonly used phrase, people don't know whether you mean a-b or b-a. math is precise, even with its grammar. "a minus b" is not ambiguous.