30 Out of 40 as a Percentage

What is 30 out of 40 as a percentage?
Percentage = Relative ValueReference Value x 100
30/40 as a percent = 30/40 x 100
= (3 x 10)/(4 x 10) x 100
= 3/4 x 100
= 3 x 25
= 75
30/40 as a percentage is 75%.