02-Abacus Basic Sums Welcome to your 02-Abacus Basic Sums 1. 2 + 7 - 62. 1 + 8 - 63. 2 + 7 - 84. 2 + 2 - 35. 3 + 6 - 46. 3 + 5 - 67. 1 + 2 - 28. 2 + 1 + 59. 1 + 6 - 210. 2 + 2 - 111. 6 + 2 - 712. 3 + 5 - 713. 3 + 6 - 414. 2 + 7 - 415. 4 + 5 - 12 out of 1