X- 15% X = 68 3.5X+ 1.8 = 12.3 3.6x÷2 = 2. 16 0.8X-4 = 1.6

5x÷2 = 10 X-0.25 X = 3 4+0.7 X = 102 X-0. 125 X = 8 X-0.375 X = 3/4

5 X-2.4×5 = 8 15x÷2 = 60 4X+X = 3. 15 3.4X+ 1.8 = 8.6

5X-X = 2.4 1.5X-X = 1 6.6X-6X = 1.8x-0.8x = 16+6

X+25% X = 90 12x = 300-4x 30÷X+25 = 85 4 10-3x = 170 3(X+0.5)= 2 1 0.5x+8 = 43 6X-3x = 18 1.5x+ 18 = 3x 5×3-X÷2 = 8 995

Second, off-type calculation (mixed operation problem and simple operation problem):

0.4× 125×25×0.8

1.25×(8+ 10)

9 123-( 123+8.8)

1.24×8.3+8.3× 1.76

9999× 100 1

14.8×6.3-6.3×6.5+8.3×3.7

1.24+0.78+8.76

933- 157-43

482 1-998

32× 125×25

9048÷26

288 1÷ 43

3.2×42.3×3.75- 12.5×0.423× 16

1.8+ 18÷ 1.5-0.5×0.3

6.5×8+3.5×8-47

(80-9.8) × 2/5- 1.32

8×7 4÷[ 1÷(3.2-2.95)]

2700×(506-499)÷900

33.02-( 148.4-90.85)÷2.5

( 1÷ 1- 1)÷5. 1

18. 1+(3-0.299÷0.23)× 1

I hope it helps you! ! !