To find the percent, first divide the part by the whole.
[tex] \frac{Part}{Whole} = \frac{15}{50} [/tex]
Now divide:
[tex] 15 \div 50 = 0.3 [/tex]
You have your answer as a decimal. To change your decimal into a percent, move the decimal point 2 places to the right and add a percent sign.
First move the decimal point:
[tex] 0.3 \rightarrow 30 [/tex]
Now add the percent sign:
[tex] 30 \rightarrow 30 \% [/tex]
30% of 50 is 15