简便计算分类练习题第一种(300+6)x1225x(4+8)125x(35+8)(12+24+80) X 5032 X (25+125)25X(24+16)4X (25X 65+25X 28)(13+24)x898X 199第四种99X13+1358X 9825+199X2579X 42+79+79 X 5775X 27+19X 2 5第五种88X125125X32X8138X 25X 484X 36+64X 8431 X 870+13 X 31072X12575X 24 25X32X125(13 X 125) X (3 X 8)75X 99+2X 7578X4+78X3+78X375X 2412X 2550X (34 X 4) X 325X 32X 125第二种84x101504x2578x10225x204704X 2588X 125102X 76101X 87第三种99x649