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Simple algebraic question

  • Thread starter L²Cc
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Simple algebra question

Homework Statement


In a biology class of s students, there are m microscopes available. if the instructor assigns one micrope to each student, 6 more microscopes will be needed. If the instructor had twice as many microscopes available and assigned one microscope to each student, 6 microscopes would be left over. What is the value of s?

Homework Equations




The Attempt at a Solution


I solved for s by "guess + check". I tried expressing the word problem algebraically, but I can't seem to get it right. I get a negative instead of a positive value, so I find the absolute value and end up with the final results. Yet, I'm sure there is another way out.
Here are my equations:
sm=m-6
Hence, s= (-6/m)
Second equation,
2ms=m+6
Then I do substitution and get -18??!
Also, my equations don't really illustrate what is described above.
 
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Answers and Replies

  • #2
arildno
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"In a biology class of s students, there are m microscopes available. if the instructor assigns one micrope to each student, 6 more microscopes will be needed."

How is s and m related here? What equation does this wordiness reduce to?

"If the instructor had twice as many microscopes available and assigned one microscope to each student, 6 microscopes would be left over."

And here? What is the equation?
 
  • #3
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Why is there a product of s and m?

In the first case, there are six students more than the number of microscopes available, i.e. the difference between the number of students and microscopes is 6.

s - m = 6


Now, can you get the second equation?
 
  • #4
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equation for second situation: s=2m-6
Thank you!
 
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  • #5
arildno
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Indeed!
So, start solving the system.
 
  • #6
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just by looking does s=18
 
  • #7
arildno
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just by looking does s=18
Let OP manage something on his own, okay?

Besides, he has already "guessed&checked"
 
  • #8
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Besides, he has already "guessed&checked"
arildno, it's (I'm) a she, and I did solve the system! Thank you!
 
  • #9
arildno
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arildno, it's (I'm) a she, and I did solve the system! Thank you!
Dear me. With such a masculine user name, I would never have guessed that.
 
  • #10
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:wink: !!!
 

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