What Is 10% Out Of 1800?

"Percent" means "per hundred", so 10% is 10/100.

10% of 1800 = (10/100)*(1800)
  = 10*(1800/100) = 10*18 = 180

10% of 1800 is 180
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"Of" indicates "times"; "per" indicates "divided by".
10 per hundred is 10/100.

180 is 10 percent of 1800

I hope that this helps you