X－ 2 7 X= 4 3 2X + 2 5 = 3 5 70%X + 20%X = 3.6 X× 5 3 =20× 4 1 25% + 10X = 5 4 X - 15%X = 68 X＋ 8 3 X＝121 5X－3× 21 5 ＝ 7 5 3 2 X÷ 4 1 ＝12 6X＋5 =13.4 8 3 4 1 4 3   X 3X= 8 3 X÷ 7 2 = 16 7 X＋ 8 7 X= 4 3 4X－6× 3 2 =2 12 5 ÷X= 3 10 5 3 X = 72 25 9 8 X = 6 1 × 51 16 X÷ 35 6 = 45 26 × 25 13 4x－3 ×9 = 29 2 1 x + 6 1 x = 4 10 3 X－21× 3 2 =4 20 4 1   x x 8 ) 6 .2 ( 2   x 6X＋5 =13.4 2 5 X- 1 3 X= 3 10 4χ －6＝38 5X= 19 15 21 8 X= 15 4 X÷ 5 4 = 28 15 3 2 X÷ 4 1 =12 5 3 X= 72 25 9 8 X= 6 1 × 51 16 X÷ 35 6 = 45 26 ÷ 25 13 X-0.25= 4 1 4 X =30% 4+0.7X=102 3 2 X+ 2 1 X=42 X+ 4 1 X=105 X- 8 3 X=400 X-0.125X=8 X 36 = 4 3 X+ 3 7 X=18 X×( 1 6 + 3 8 )= 13 12 x－0.375x= 6 5 x× 3 2 + 2 1 =4× 8 3 X－ 7 3 X＝12 5 X－2.4×5＝8 0.36×5- 3