Why is the LCD of 5/2x and 7/5x3y 10x^2y and not 10x3y?

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Homework Help Overview

The discussion revolves around finding the lowest common denominator (LCD) of the fractions 5/2x and 7/5x3y. Participants are examining the discrepancy between their calculations and the answer provided in a textbook.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants are exploring the calculation of the LCD, with some suggesting that the correct answer should be 10x3y, while others question whether the textbook might contain a typo. There is also a discussion about the interpretation of the expressions involved.

Discussion Status

The conversation is ongoing, with participants sharing their interpretations and calculations. Some have offered potential explanations for the discrepancy, such as the possibility of a typo in the textbook, while others are confirming their understanding of the problem setup.

Contextual Notes

There is mention of a potential typo or printing error in the textbook, which may have contributed to the confusion regarding the correct LCD. Participants are also reflecting on the clarity of the expressions used in the problem.

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Homework Statement



LCD of 5/2x and 7/5x3y

Homework Equations



Lowest common denominator is also lowest common multiple:

(2)(x)
(5)(x)(3)(y) =
(10)(x)(3)(y)

I figured, the lowest common multiple of 2x and 5x3y is 10x3y. For some reason, my book shows the answer as 10x^2(y)!

The Attempt at a Solution



At this point, I don't know why I didn't come up with the same solution as the book.This is from the Pre-Algebra text "Preparation for Algebra" Nanney/Cable. I bought this from my college to brush up on a lot of fundamental skills I'd forgotten and this was an exercise in the beginning of the book. Is it a typo or am I just going crazy?
 
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Do you mean
[tex]\[<br /> \frac{5}{{2x}}\quad and\quad \frac{7}{{5x3y}}<br /> \][/tex]

If so, then LCD is [tex]\[<br /> 2 \cdot 3 \cdot 5 \cdot xy<br /> \][/tex]
 
Yeah, I agree with 30xy if the denominators are 2x and 15xy each...
 
marcflores said:

Homework Statement



LCD of 5/2x and 7/5x3y
...

I figured, the lowest common multiple of 2x and 5x3y is 10x3y. For some reason, my book shows the answer as 10x^2(y)!
...
Is it a typo or am I just going crazy?
It's either a typo or poor quality printing.

Does [itex]5x^2y[/itex] look a little bit like [itex]5x3y[/itex]? I'll bet the book meant the former.
 
symbolipoint said:
Do you mean
[tex]\[<br /> \frac{5}{{2x}}\quad and\quad \frac{7}{{5x3y}}<br /> \][/tex]

If so, then LCD is [tex]\[<br /> 2 \cdot 3 \cdot 5 \cdot xy<br /> \][/tex]


Yes, that's how I meant it. But I also agree with Gokul43201 in that it might be a typo or poor printing because it seems that all the other exercises in the section have a certain likeness to it... this one seemed off.

Thanks for the help.
 

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