If a weighted score for a project is based on just two criteria, fit with strategy, weighted 70% and roi, weighted 30%, what would be the weighted score for a project with scores of 80 on fit with strategy and 50 on roi?

When dealing with weighted averages, we multiply the score of each item by the percentage that it's been weighted and add the scores together. 80/100 X 70/100 = 5600/10000 or 56/100 50/100 x 30/100 = 1500/10000 or 15/100 56 + 15 = 71 and so your grade would be 71%