80 out of 100 means 20 wrong answers
Scoring 80 out of 100 is the same as getting 20 wrong out of 100. Both describe one result: 80 correct answers on a 100-question test. Whether your teacher counts up from correct answers or down from wrong ones, the percentage is identical.
How the 80 out of 100 percentage is calculated
The percentage comes from one division: 80 Γ· 100 Γ 100 = 80%. Every question on a 100-question test is worth 1% of the total score.
Why 80% is a B on the standard scale
The standard 10-point scale puts a B between 80% and 89%, so a 80% test earns a B. That converts to a 3.0 on the 4.0 GPA scale.
How many can you miss on a 100-question test?
Every letter grade on a 100-question test has a maximum number of wrong answers.
Letter grade cutoffs for a 100-question test
- A β at least 90 correct (miss no more than 10 questions)
- B β at least 80 correct (miss no more than 20 questions)
- C β at least 70 correct (miss no more than 30 questions)
- D β at least 60 correct (miss no more than 40 questions)
Anything at or below 59 correct falls under 60% and is an F on this scale. Your own class may round differently or use a curve, so treat these cutoffs as the common default rather than a rule.