①3600÷8÷125
②125×32×25
③156×63+156×36+156
④68×25
⑤600-139-61
⑥79×99
111÷3=37 222÷6=37 333÷9=37
444÷□=37 555÷□=37 666÷□=37
□÷21=37 □÷24=37 □÷□=37