times 20=-|||-times 120=-|||-times 30=-|||-times 20=-|||-.times 20=-|||-times 230=-|||-times 40=-|||-times 25=

步骤 1：计算 $420\times 20$
$420\times 20 = 8400$

步骤 2：计算 $50\times 120$
$50\times 120 = 6000$

步骤 3：计算 $130\times 30$
$130\times 30 = 3900$

步骤 4：计算 $120\times 20$
$120\times 20 = 2400$

步骤 5：计算 $190\times 20$
$190\times 20 = 3800$

步骤 6：计算 $30\times 230$
$30\times 230 = 6900$

步骤 7：计算 $140\times 40$
$140\times 40 = 5600$

步骤 8：计算 $400\times 25$
$400\times 25 = 10000$