How do you find percent of 840?

One percent of 840 is one hundredth of 840, or 1/100 x 840

That's 8.4

5 percent (5%) of 840 is five hundredths of 840

That's 8.4 x 5 = 42

12 percent (12%) of 840 is twelve hundredths of 840

That's 8.4 x 12 = 1008

And so on.