1.688×32≈54.02, 1.688 × 32 3376 50 46 54.016 ;29.9÷0.46=65.00,2.6×0.25=0.650, 2.6 ×0.25 1 30 5 2 0.6 50 ;0.77×0.35≈0.270, 0.77 ×0.35 3 85 231 0.2695 .