Math
posted by Sue on .
I'm confused.Can someone tell me if I have done this correct.I'm trying to get the average using a weighted scale:
TOTAL GRADES: WEIGHT
90%  5%
100% 15%
95%  15%
90% 5%
94.5% 60%
I multiplied the total grade by the percent, then added the percent. But I get 109.20 as a final grade but I know that can be right...please help me. Thanks

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

thanks for your help