$2500/2 = 1250. 1250/2 = 625. 625/2 = 312.5. 312.5/2 = 156.25. 156.25/2 = 78.125. 78.125/2 = 39.0625 Add all the end numbers up = 2460.9375. 2460.9375/2 = 1230.46875. 2460.9375 - 1230.46875 = 1230.46875. Therefore, she payed back 1230.46875, meaning she had 1230.46875 left in her account. Hope i helped! :D