Nick saved $5 in the first week and increased his savings by $5 each week. How much would he have saved at the end of 9 weeks?
Make a list: 5, 10, 15, 20, 25, 30, 35, 40, 45
Using rainbow method: 5 + 45 = 5010 + 40 = 5015 + 35 = 5020 + 30 = 50Sum of each pair = 50Number of pairs: 4, left: 25 Sum of all pairs = [50 x 4] + 25 = 200 + 25 = $225 Answer(s): $225
