Reflection 1: What would be another way to calculate total interest rather than merely using =sum(?

Reflection 2: When was the original principal invested and when was the payment invested (end or beginning of the period)? In the finance world, what type of investment is this called?

Reflection 3: What are some of the pros and cons to each of the three methods you have used?

Givens: Line Number 25 Principal 845.00 Payment 88.00 APR 6.50% Compounds 12 Month Principal Interest Payment Methods 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 86.00 937 58 1030.66 112424 1218.33 131293 140804 1503.67 1599.81 1696.43 1793.67 189138 1989.63 2088.40 2187.72 228757 238796 2488.89 259037 269240 279499 2898.13 300183 3106.09 321091 3316.30 342227 3528.80 363592 3793.61 385189 3960.75 4070.21 4180.26 4290.90 4402.14 Total: 458 5.08 5.58 6.09 6.60 7.11 7.63 3.14 8.67 9.19 9.72 10.24 10.78 11 31 11.85 1239 12.93 13.48 1403 1458 1514 15.70 16.26 1682 1739 1796 18.54 19.11 19.69 20.28 20.86 2145 2205 2264 23.24 23.84 500.99 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 88.00 3168.00 Total 845.00 937 58 1030.66 112424 1218.33 131293 1408.04 1503.67 1599.81 1696.48 1793.67 189138 1989.63 2088.40 2187.72 228757 238796 2488.89 259037 269237 2692.40 279499 2898.13 300183 3106.09 3210.91 3316.30 342227 3528.80 363592 3743.61 385189 3960.75 4070 21 418026 4290.90 4513.99 Month #18 Iterations (Steps) "=C27-027-E27 Month #18 Formula (Regular Payments) 259037 "=945' (1-065/12 18-88*((1-0,065/1218-1(0.055 Month #18 Excel Function 2590.37 EF(D5 D6 B27 D4 D3)