2.1.234a =1.23a+0.3a = 750 Correct result 925.5.
3. For the 2005th time, pour 1/2006 from Cup A into Cup B, and the water in Cup B is
1/2 * 2/3 * * 2005/2006 =1/2006, so the weight of a glass of water is 2005/2006.
4. Let x 1, x2 and x3 have x1=1/4 * (x2+x3+200), x2 = 2/7 * (x 1+x3+200), and x3 = 5/7.
Write so little first, then do it ~