<span>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%</span>
As first term in sequence is 3 so multiplying it by common ratio 5 we get 15, then multiplying 15 by 5 we get 45 and so on the sequence is <span>3,15,45,225</span> whose sum is 288
