After writing my bit about how to figure out what grade you need to pass your class, I thought some more and realized that while everything in it is true, it’s not necessarily helpful, because people get panicky at formulas. So I thought to make up some tables showing what you need, if you go in with a certain grade, to pass, or get a B, or an A, or what not, for different weightings of the final exam. That’s easy enough to do especially once I set up a Matlab (well, an Octave) script to build the tables for me.

In these tables, the row is your current score, and I should clarify that’s your percentage score. This doesn’t have anything directly to do with the number of points you might have got on different assignments because not all points carry the same weight: ten points on your midterm (probably) counts for more than ten points on homework number three out of twelve assignments. And, obviously, I’m not listing all the possible percentage scores you might have going into the final because that produces a table that’s boringly long. The column is what score you want to get, and I picked 60, 65, 70, 80, and 90 as the most likely useful targets.

The tables were easiest to read by making a new table for each of the different weightings I considered. So there’s one table for final exams worth 1/3rd of the class grade, one for finals worth 30 percent, for finals worth 25 percent, and for finals worth 20 percent. None of these consider any extra credit you might have gotten, or extra penalties drawn because you couldn’t put the cell phone down for 75 minutes of class, but this will at least let you get close to knowing how well you have to do. The final’s weight could be anything, I admit, but these seemed like the most likely values to come up; if there’s a lot of demand to work this out for, say, a final worth 40 percent of the course let me know and I’ll add that in.

To use the tables, go to the table for your class’s weighting, then look to the row with whatever’s the best fit for your pre-final percentage, and then across to the column matching what score you need.

For example, if your final is one-third the course average, and you’ve got an 84 going in, and you want a 90 in the course, then, that’s the first table, and the fourth row (matching a percentage of 85), and the last column in that: aim to get at least 100 … well, that’s a long shot, but you are trying to go from an 84 up to a 90 with one exam. If the final is 20 percent of the course grade, and going in to the final you have 66 percent, and you want to get at least a C, 70 percent, then that’s going to the last of these tables, and to the row starting 65, and across three columns: you need about a 90. Good luck.

And, yes, if you’re going in with a great score and just want to pass you can be in a quite comfortable position. Suppose the final is 25 percent of the course grade, you’re going in with 89 percent, and all you want to do is pass. The 25-percent table shows that you need a score of about -30 on the exam so you could just sleep in and skip the whole business, but your instructor will be quite disappointed in you if you do.

## Final Worth 40 Percent (2/5) Of The Course Score:

To Get | |||||
---|---|---|---|---|---|

60 | 65 | 70 | 80 | 90 | |

If You Have | Requires | ||||

100 | 0 | 12 | 25 | 50 | 75 |

95 | 7 | 20 | 32 | 57 | 82 |

90 | 15 | 27 | 40 | 65 | 90 |

85 | 22 | 35 | 47 | 72 | 97 |

80 | 30 | 42 | 55 | 80 | 105 |

75 | 37 | 50 | 62 | 87 | 112 |

70 | 45 | 57 | 70 | 95 | 120 |

65 | 52 | 65 | 77 | 102 | 127 |

60 | 60 | 72 | 85 | 110 | 135 |

55 | 67 | 80 | 92 | 117 | 142 |

50 | 75 | 87 | 100 | 125 | 150 |

45 | 82 | 95 | 107 | 132 | 157 |

40 | 90 | 102 | 115 | 140 | 165 |

35 | 97 | 110 | 122 | 147 | 172 |

30 | 105 | 117 | 130 | 155 | 180 |

## Final Worth 1/3 Of The Course Score:

To Get | |||||
---|---|---|---|---|---|

60 | 65 | 70 | 80 | 90 | |

If You Have | Requires | ||||

100 | -20 | -5 | 10 | 40 | 70 |

95 | -10 | 5 | 20 | 50 | 80 |

90 | 0 | 15 | 30 | 60 | 90 |

85 | 10 | 25 | 40 | 70 | 100 |

80 | 20 | 35 | 50 | 80 | 110 |

75 | 30 | 45 | 60 | 90 | 120 |

70 | 40 | 55 | 70 | 100 | 130 |

65 | 50 | 65 | 80 | 110 | 140 |

60 | 60 | 75 | 90 | 120 | 150 |

55 | 70 | 85 | 100 | 130 | 160 |

50 | 80 | 95 | 110 | 140 | 170 |

45 | 90 | 105 | 120 | 150 | 180 |

40 | 100 | 115 | 130 | 160 | 190 |

35 | 110 | 125 | 140 | 170 | 200 |

## Final Worth 30 Percent (3/10) Of The Course Score:

To Get | |||||
---|---|---|---|---|---|

60 | 65 | 70 | 80 | 90 | |

If You Have | Requires | ||||

100 | -33 | -16 | 0 | 33 | 66 |

95 | -21 | -5 | 11 | 45 | 78 |

90 | -10 | 6 | 23 | 56 | 90 |

85 | 1 | 18 | 35 | 68 | 101 |

80 | 13 | 30 | 46 | 80 | 113 |

75 | 25 | 41 | 58 | 91 | 125 |

70 | 36 | 53 | 70 | 103 | 136 |

65 | 48 | 65 | 81 | 115 | 148 |

60 | 60 | 76 | 93 | 126 | 160 |

55 | 71 | 88 | 105 | 138 | 171 |

50 | 83 | 100 | 116 | 150 | 183 |

45 | 95 | 111 | 128 | 161 | 195 |

40 | 106 | 123 | 140 | 173 | 206 |

## Final Worth 25 Percent (1/4) Of The Course Score:

To Get | |||||
---|---|---|---|---|---|

60 | 65 | 70 | 80 | 90 | |

If You Have | Requires | ||||

100 | -60 | -40 | -20 | 20 | 60 |

95 | -45 | -25 | -5 | 35 | 75 |

90 | -30 | -10 | 10 | 50 | 90 |

85 | -15 | 5 | 25 | 65 | 105 |

80 | 0 | 20 | 40 | 80 | 120 |

75 | 15 | 35 | 55 | 95 | 135 |

70 | 30 | 50 | 70 | 110 | 150 |

65 | 45 | 65 | 85 | 125 | 165 |

60 | 60 | 80 | 100 | 140 | 180 |

55 | 75 | 95 | 115 | 155 | 195 |

50 | 90 | 110 | 130 | 170 | 210 |

45 | 105 | 125 | 145 | 185 | 225 |

## Final Worth 20 Percent (1/5) Of The Course Score:

To Get | |||||
---|---|---|---|---|---|

60 | 65 | 70 | 80 | 90 | |

If You Have | Requires | ||||

100 | -100 | -75 | -50 | 0 | 50 |

95 | -80 | -55 | -30 | 20 | 70 |

90 | -60 | -35 | -10 | 40 | 90 |

85 | -40 | -15 | 10 | 60 | 110 |

80 | -20 | 5 | 30 | 80 | 130 |

75 | 0 | 25 | 50 | 100 | 150 |

70 | 20 | 45 | 70 | 120 | 170 |

65 | 40 | 65 | 90 | 140 | 190 |

60 | 60 | 85 | 110 | 160 | 210 |

55 | 80 | 105 | 130 | 180 | 230 |

50 | 100 | 125 | 150 | 200 | 250 |

45 | 120 | 145 | 170 | 220 | 270 |

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Reblogged this on nebusresearch and commented:

And this post makes matters a little bit simpler, by showing charts of what minimum scores one needs on the final to get various minimum scores, for different final exam weightings. And, yes, if you’re going into a final exam with a high enough average, it’s conceivable that you could pass, or even get a better-than-passing, score with a zero on the final. Don’t do that. It makes your instructor sad. Just be less tense about the final instead.