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Below is my problem:

$$2 \times A \times 2.5 = 1500 \times 1/48$$

How do they get $A=2$ two in the above formula? I'm getting 6.25.

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    Are you saying that "they" claim $A=2$? – 2017-02-06
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    If you mean $$A\times 2\times 2.5=\frac{1500\times 1}{48}$$ the answer is definetely $A=6.25$. – 2017-02-06
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    It sounds a lot like you might be withholding relevant information. Are you *sure* there isn't more to the problem? For instance, do these computations involve units of measure? We can confirm that your random, out-of-context equation ought to have the solution $A=6.25$, but not much is gained in the way of figuring out why the problem is different than you expect. – 2017-02-06
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    @rschweib - the question seemed clear to me! Was it about mathematics? Yes. Was the question clear? I don't see why not. Was there evidence of questioner effort? Yes. I don't see why it was out-of-context or 'random' – 2017-02-06
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    Who is/are "they"? – 2017-02-06
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    $2*A*2.5=1500*\frac 1{48} \implies 2A*(\frac 52)=5*300*\frac{1}{48} \implies 5A = 5*100*3\frac {1}{3*16} \implies A = 100*\frac {1}{16}$. So the answer would have been $2$ if it had be $2*A*2.5=1500*\frac 1{150}$. I imagine there was a typo somewhere. – 2017-02-06
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    @Cato Before *you* start judging rschwieb, let me say, the question is natural: rschwieb is only asking because the discrepancy between our results here to the posted equation, and the answer some entity referred to only as "they" claimed the answer is $2$, which makes asking the OP about missing information, legitimate. Note, there is either a typo in "their question" (their referring to the mysterious being "they"), or a typo in the OP's question. – 2017-02-06
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    I presume 'they' is a model answer in a book! Maybe i'm presuming wrong of course. – 2017-02-06
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    @Cato Th question is "clear" but the OP's difficulty is not one of math as the OP vdemonstrated the abillity to do a question correctly. The difficulty is confusion as to why an authoritative source gave a seemingly incorrect answer. We do want to help and we do find incorrect authority frustrating. So we want to figure out in contest if something else was meant. "You are right, the book is wrong" is slightly satisfying but we do worry that there is something more we/the op may be missing. – 2017-02-06
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    @Cato By not identifying who "they" refers to is one example of missing context. When someone posts a question asking why "their" solution (?) differs from the OPs solution, there is nothing out of line when one asks for the source, and/or missing information. – 2017-02-06
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    The poster is a beginning student, in junior high school or an upgrading class, so this is probably a random question from a text or class or homework. Students are always asked to do work totally out of context - that is one of the problems with the math curriculum - so that is not the poor kid's fault. The random "they" who say that A = 2 would be some kind of answer key. Referring to "they" or "it" without reference is a bad habit which students are allowed to continue far too long. I was severely criticized by a calculus student just yesterday for asking that things be written in math. – 2017-02-06
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    As written, yes A = 6,25 Common sources of error: Omitting parentheses Omitting parts of equations Order of operations Misunderstanding notation for example roots and exponents – 2017-02-06
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    @victoria - I don't know if he's a school kid or not - I don't know how to find that on his profile. Could he just as well be a 96 year old man? I can't see how we could know differently. – 2017-02-06
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    Cato -- age is not obvious but clearly a beginner and thus due some understanding and explanation. – 2017-02-06
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    As written, yes A = 6.25 $\\$ $\\$ Common errors:$\\$ (from a long career as a teacher - tutor) $\\$ $\\$ Parentheses $\\$ Omitting parts $\\$ Order of operations$\\$ Misunderstood notation (example roots, exponents)$\\$ Signs $\\$ Bad handwriting,example 4 or 9, s or 5, + or t, 1 or L etc.$\\$ Omit decimal $\\$ Wrong question or page/section number $\\$ $\\$ If you have double-checked all of the above and have asked people as here and have gone back and triple-checked, yes, sometimes answer keys are wrong. Online answer keys are as much error-prone as everything else online. – 2017-02-06
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    @victoria And on to the end of that list I'd add the thing I was mentioning about units: For example, the expressions $36A=3\implies A=1$ is nonsense if the author doesn't mention that the book actually says $36\,in\cdot A=3\,ft$ means that $A=1$. – 2017-02-06
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    @Cato Others have already done a great job at interpreting the intentions of my comment. It is partly criticism, yes, but I hope upon rereading it you can see how it is intended to help the poster get to the bottom of the mystery, and that it's very reasonable to point out what I was pointing out. – 2017-02-06

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It may very well be 1500 * 1/150, as that explains how A = 2. Everyone, including myself, ended up with 6.25 based on the math you presented us. It would make the most sense for this to be a typo. If this is school work, inform your teacher.