# Math

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I'm confused.Can someone tell me if I have done this correct.I'm trying to get the average using a weighted scale:
90% ---------- 5%
100% ---------15%
95% --------- 15%
90% -----------5%
94.5% --------60%

• Math -

90+100+95+90+94.5 = 469.5
469.5/5 = 93.9 = average grade without weighting.(weight of .20 or 20% for each)
now do it with weighting
90*.05 +100*.15+95*.15+90*.05 +94.5*.60= 90.9 with weighting

• aritmetic error -

90*.05 +100*.15+95*.15+90*.05 +94.5*.60= 90.9 = 94.95

• Math -

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