一、解方程.
3X= X÷ = 125 ÷X=310
=30% X = X-0.25=
x09
X× =20× x09 50% X + X = 3.6 25% X + 15%X =
X - 15%X = 68 X－ 27 X = X＋ X＝121
X＋ X= X + X = 4 X+ X=20
6X＋5 =13.4 4 X－6＝38 X+ =
4 X－3 ×9 = 29 5X－3× ＝ 4X－6× =2
0.36×5- 34 X = 35 X - 0.8 X = 16+6 23 ( X - 4.5) = 7
X÷ ＝12 2(X-2.6)=8 25 X-13 X=310
X×( 16 + 38 )=1312 X－0.375 X = x0920 X– 8.5= 1.5
X - 45 X -4= 21 4+0.7X=102 12 X - 25% X = 10
二、简便运算.
（712 - 15 ）×60 36×3435 0.65×101
（1.25-0.125）×8 2538 ×8 24×( - - - )
(12+ ) ×7 13×10.2 2.6×99
47 ×613 +37 ×613 27.5×3.7-7.5×3.7 ÷ + ×
710 ×101- 710 35 × 99 + 35 × - ÷
x09x09
×103- ×2- 0.92×1.41＋0.92×8.59
2.25×4.8+77.5×0.48 4.8×7.8+78×0.52 1.3×11.6－1.6×1.3
227 ×(15×2728 )×215 4.36×12.5×8 2.5×32×1.25
1.25÷ ×0.8 9.6÷3.2÷3 15.2÷0.25÷4
89 ×89 ÷89 ×89 ×3÷ ×3 146.5-（23+46.5）
12.89-(3.89-1.6) 73.8-1.64-13.8-5.36 15.75+3.59-0.59+14.25
125×36×25 31/30×31 200.2 ×20.01-200.1 × 19.99 2010/2011×2012 32×30/31+1/30
5.48-（9.4-0.52） 12.06＋5.07＋2.94x09 30.34＋9.76－10.34