2400÷6－45 800× 7－180 1600÷2＋230

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4000 ÷ 8 + 350 320÷8＋64 270 ÷ 3 ×9

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630 ÷ 9 + 320 2800+32× 6 300÷6×9

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= = =

(6900-2400)÷ 5 （72÷9）÷(56÷8) 54 ÷ 9 ×8

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280× 4 ÷5 60×8+1570 60×(23-17)

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22×4＋221 21×3＋410 40÷2＋174

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= = =

147＋72÷8 9×4＋420 2×80÷4

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= = =

120×5÷2 202＋36÷9 30÷5＋240

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