**So, it's report card time soon. And I'm sure that I'm not the only one to calculate my overall average as soon as I get all my marks! But does everyone do it the**

*right*way?

**Okay, let's make a situation with my friend Bob:**

**Bob's school has a 6-day cycle system.**

**Bob's got 5 different courses.**

**Here are Bob's courses and marks:**

**Math: 81%****French: 68%****English: 87%****Science: 73%****P.E.: 95%**

**Bob has Math and English 6 times a cycle (100% of the cycle);**

**he has French and Science 4 times a cycle (let's say 67% of the cycle) and**

**he has Physical Education once a cycle (let's say 17% of the cycle).**

**Bob here wants to know his overall average and doesn't have the patience to wait for the Honor Rolls, if he's even on it (we'll solve this mystery,**

*Scooby!*).

**So this is da' formula you's gonna use Bobby:**

**where "T" is the total percentage (overall; in %), "P" is the percentage for a class and "C" is the percentage of the number of classes you have for that course for a cycle.**

**Let's fill in the blankies, shall we?**

**T = (81•100)+(68•67)+(87•100)+(73•67)+(95•17)/(100+67+100+67+17)**

**T = (8100)+(4556)+(8700)+(4891)+(1615)/(351)**

**T = (27 862)/(351)**

**T = 79.37%**

**Bob is still not satisfied! He wants to know why he has such a low mark in French. Luckily this also works for competencies―and much more!**

**So, let's see. There are two competencies: Talking (worth 45%) and writing/comprehending (worth the other 55%). For these competencies, he got 83% and 56%. That 83% is why he's so astonished about his mark! Let's see here:**

**T = (P1•C1)+(P2•C2)/(C1+C2)**

**T = (83•45)+(56•55)/(45+55)**

**T = (3735)+(3080)/(100)**

**T = (6815)/100**

**T = 68.15%**

**Now Bob has nothing to whine about and is satisfied! :)**

**Are**

*you*satisfied?
Excellent process, perfect formula, great examples. I always like to look at the result of a weighted average and ask myself "Which nbr should the result be closest to?" and it's usually the one with the heaviest weight. SO his 79% is good because he has some 80's that are heavy! The only thing I would change would be to use codecogs for your fractions!

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