SOLUTION: Less than half the students missed the chemistry demonstration. In fact only 3/10 of the students missed the demonstration. If 21 students did not miss the demonstration, how many

Question 333673: Less than half the students missed the chemistry demonstration. In fact only 3/10 of the students missed the demonstration. If 21 students did not miss the demonstration, how many students did miss the demonstration?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Less than half the students missed the chemistry demonstration.
In fact only 3/10 of the students missed the demonstration.
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7/10 of the students did not miss the demonstration.
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If 21 students did not miss the demonstration, how many students did miss the demonstration?
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Let "x" be the number of students:
Equation:
(7/10)x = 21
(1/10)x = 3
x = 30 students did not miss the demonstration
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# who missed the demonstration = (3/10)*30 = 9
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Cheers,
Stan H.
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Cheers,
Stan H.

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