Thereare 30 students in mr. holland's music class. if 30% of the students play in the school band, how many students in the class play in the school band

9 students in the class play in the school band. 

30% of 30
Well, when doing a percentage you first turn the percentage into a decimal (move the % two units to the left). So 30% = 0.3

In math, the word of  means multiplication, so: 0.3 x 30 
Which equal 9. 

You can also turn the percentage into a fraction, it's really up to preference. 

30/100 of 30 = 3/10 of 30 = 3/10 x 30 = 3/10 x 30/1 = 9/1 or 9

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