( 140-70)×54 63+84×2÷42 490÷7+24×5

26×6- 1 10 345+99 (46-20)×30-90

25×27×4 15×7+85×7 (40-4)×25

125×64 2400÷80- 14×2 108-(83+360÷60)

(420+48)÷(375-345) 290-(34×3+99)

142-54÷9+ 14 240÷ 16 75×4×25

407-99 16×76-76×6 99×53+53

720÷36÷2 103×35 450-2×( 16+9)

245-(45+39) 28×25 473+59+27+ 1

98×99 125×(8×4)×5 4 1×25-25

88× 125 420÷(205- 198)×4 540÷2÷54

460 ÷ (29-18 ÷ 3) 720 ÷ 36 (960-400) ÷ 70 ÷100 is too much, that's all. If you really want to practice, you can just find a few numbers, add, subtract, multiply and divide them, and then put them in brackets.