12×103-4500÷75 ×[÷(×)]
304-275÷(275÷25) (252-14)÷17-10
7.9×11-7.9 0.99×9+0.99
199.8×19.99-199.9×19.97 (10-100÷10)×11=
4.83×0.59+0.41×1.59-0.324×5.9 (346-10)÷16-12
49×50≈ 89×41≈ 10×42≈ 20×32≈ 10×21≈ 30×32≈