1、一、解方程。 姓名： 3X= X= X= 25% X + 15%X = =30% X = X-0.25= 50% X + X = 3.6 X=20 X - 15%X = 68 X X = XX121 XX= X + X = 4 X+X=20 4X6=2 6X5 =13.4 4 X638 X+= X - 0.8 X = 16+6 4 X3 9 = 29 5X3 0.365- X = 4+0.7X=102 ( X - 4.5) = 7 X12 2(X-2.6)=8 X-X=X( + )= X0.375 X = 20 X 8.5= 1.5 X - 25% X = 10 X - X -4= 21 二、
2、简便运算。（- ）60 36 0.65101（1.25-0.125）8 258 24(-) (12+) 7 1310.2 2.699 + 27.53.7-7.53.7 +101- 99 + -103-2- 0.921.410.928.59 2.254.8+77.50.48 4.87.8+780.52 1.311.61.61.3 (15) 4.3612.58 2.5321.25 1.250.8 9.63.23 15.20.254 33 146.5-（23+46.5） 12.89-(3.89-1.6) 73.8-1.64-13.8-5.36 15.75+3.59-0.59+14.255.48-（9.4-0.52） 12.065.072.94 30.349.7610.34
