130 * 204 - 168 * 4 - 2900 = 130 * 51 * 4 - 168 * 4 - 2900 = 4*( 130 * 51 - 168 ) - 2900 = 4 * ( 6630 - 168 ) - 2900 = 4 * 6462 - 2900 = 25848 - 2900 = 22948
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309 * 65 - ( 3000 - 37 * 30 ) = 309 * 65 - ( 3000 - 1110 ) = 309 * 65 - 1890 =
= 20085 - 1890 = 18195
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1040 : 20 * ( 140 + 260 ) - 9908 = 52 * 400 - 9908 = 20800 - 9908 = 10892