Freight elevator's capacity will be defined as c.
Pounds (weight) will be defined as w.
So we can say that:
c<3000w
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Piano will be defined as 900w.
Number of crates of electronics will be defined as n300w, as we don't know how many crates there are.
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So, with this information we can say that:

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Now let's find out how many crates (n) can go on that elevator with the piano...


The elevator won't be able to accommodate a piano and 7 crates of electronics but it will be able to accommodate a
piano and 6 crates of electronics.