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

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The discussion centers on the confusion regarding the lowest common denominator (LCD) of the fractions 5/2x and 7/5x3y. The participant initially calculated the LCD as 10x3y, while the textbook states it as 10x^2y. There is speculation that the discrepancy may be due to a typo or printing error in the textbook. Participants agree that the correct LCD should involve the factors of both denominators, leading to a conclusion of 30xy if the denominators are interpreted differently. The conversation highlights the importance of clarity in mathematical texts to avoid such misunderstandings.
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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
\[<br /> \frac{5}{{2x}}\quad and\quad \frac{7}{{5x3y}}<br /> \]<br />

If so, then LCD is \[<br /> 2 \cdot 3 \cdot 5 \cdot xy<br /> \]<br />
 
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 5x^2y look a little bit like 5x3y? I'll bet the book meant the former.
 
symbolipoint said:
Do you mean
\[<br /> \frac{5}{{2x}}\quad and\quad \frac{7}{{5x3y}}<br /> \]<br />

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


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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