First translate the question into an equation.
"What percent" means x/100, "of 40" means times 40, "is 14" equals 14.
So we have (x)(40) = 14 or 40x = 14.
Dividing both sides by 40, we find that x = 0.35.
Now, we want to write our answer as a percent.
So we move the decimal 2 places to the right and we have 35%.