250 B) 2000 – 1999 + 1998 – 1997 + … + 4 – 3 + 2 – 1 C) 152

Question

Bài 3 (3đ): Tính nhanh: a) 42.187 + 563.42 + 42.250 b) 2000 – 1999 + 1998 – 1997 + … + 4 – 3 + 2 – 1 c) 152.679 + 152.322 – 152

Answer

a) 4 2 .187 + 563.4 2 + 4 2 .250