How do you turn a percent into a decimal?

1 Answer
Jan 17, 2015

Divide by 100, so #40%=0.40#

Actually the word 'percent' means 'per 100' (maybe you recognize 'cent' as '100 in a dollar/euro/whatever').
So % is just short for "/100"

You might as well write #40%# as #40/100=0.40#

To turn a fraction into a percentage, you just do the reverse:

Multiply by 100, effectively doing #0.15=15/100=15%#

It's really that easy!