Ethan saved $5 in the first week and increased his savings by $6 each week. How much would he have saved at the end of 9 weeks?
Make a list: 5, 11, 17, 23, 29, 35, 41, 47, 53
Using rainbow method: 5 + 53 = 5811 + 47 = 5817 + 41 = 5823 + 35 = 58Sum of each pair = 58Number of pairs: 4, left: 29 Sum of all pairs = [58 x 4] + 29 = 232 + 29 = $261 Answer(s): $261