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

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SUMMARY

The lowest common denominator (LCD) of the fractions 5/2x and 7/5x3y is correctly identified as 10x^2y, according to the Pre-Algebra text "Preparation for Algebra" by Nanney/Cable. The confusion arises from a potential typographical error in the book, where the answer appears as 10x^2y instead of the expected 10x3y. The calculation for the LCD involves finding the lowest common multiple of the denominators, which are 2x and 5x3y, resulting in 10x3y. Participants in the discussion confirm the calculation and suggest that the discrepancy may be due to poor printing quality.

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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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