270/305 = 88.5 but the letter grade is dependent on the grading scale. In most instances, this would be a B or B+. A particular scale could count 88.5 as a C or an A depending on where the scale breaks.
300
It is: 270/300 times 100 = 90%
270 as a percentage of 300 is 90%
Well, let's take a moment to appreciate those numbers. If we have 270 out of 300, we can see that it's a big portion, almost the whole thing. To find the percentage, we simply divide 270 by 300, which gives us 0.9. Then, we multiply by 100 to get the percentage, which is 90%. Isn't that just a happy little percentage?
300 - 30 = 270
90 is 33.333...% of 270.
270/300=0.9, therefore 270 is 90% of 300. Generally, if you want to find what percent x is of y, then do x/y, then multiply by 100 and stick a percent sign on the end!
It is: 300
135
270
270
270