一、口算。
$760 - 380 =$ $125 ÷ 5 =$ $43 + 27 =$
$630 ÷ 7 =$ $410 × 6 =$ $310 × 30 =$
$520 × 4 =$ $960 ÷ 60 =$ $85 - 70 =$
$106 ÷ 2 =$ $75 + 75 =$ $290 × 20 =$
$35 × 30 =$ $125 × 80 =$ $120 ÷ 40 =$
$990 ÷ 90 =$ $200 ÷ 4 =$ $750 × 6 =$
$240 + 160 =$ $83 - 26 =$ $260 ÷ 20 =$
$20 × 26 =$ $120 × 40 =$ $93 - 45 =$
$96 - 69 =$ $450 ÷ 90 =$ $14 × 6 =$
$246 ÷ 6 =$ $18 × 7 =$ $120 ÷ 3 =$

一、380 25 70
90 2460 9300
2080 16 15
53 150 5800
1050 10000 3
11 50 4500
400 57 13
520 4800 48
27 5 84
41 126 40

二、在$□$里填数，在$◯$里填运算符号。
$(26 + 32) × 4 = □ ◯ 4 + □ ◯ 4$
$36 × (20 + 3) = 36 ◯ □ + 36 ◯ □$
$(18 + 25) × 8 = □ ◯ 8 ◯ □ ◯ 8$
$43 × 28 + 57 × 28 = (□ ◯ □) × 28$
$125 × (80 + 2) = 125 × □ ◯ 125 × □$

二、26 × 32 ×
× 20 × 3
18 × + 25 ×
43 + 57
80 + 2