Learn what Percentage of A is B In this video we will learn what percent of A is B, how do I look at computing percentages when I'm given the values. And the question is, what percent of 320 is 80? What am I given? I need to find out what percent of 320 is 80. Well, what is a percent? A percent is a ratio comparing a number to 100. So lets say that the answer what percent, this is what we need to determine. Lets say the answer is N%, so what do we know, that if the answer is N%, N/100 is the fraction. So N% can be written as N/100, what we know is N% of 320=80, that’s what the question is telling us. What percent which is what I assumed was N, so what percent of 320 is 80 means N% of 320 is 80 or N/100 because N% can be written as N/100, N/100 of 320=80 which means N/100 multiplied by 320=80. So what am I doing, I know N×320=80×100, I simply multiplied both sides by 100 which means N=80 multiplied by 100/320 which gives me the answer 25. So if N=25, N%=25%, so the answer to the question what percent of 320 is 80, the answer is 25%. Let’s quickly recap how we do that. When given a question that says what percent of 320 is 80, I can assume that the percent is N in which case, I know that N% of 320 is 80. Now N% can be written as N/100 which when I solve gives me N×320=80, 80 multiplied by 100 which gives me N=25 or N%=25%.