自然数a÷b=5,a、b的最小公倍数是 ,它们的最大公因数是 .
= ÷ = (填小数)==.
= : =15÷ = %
= :20=4.5÷ = %=0.5 .
15÷ ==9: = %=0.75.
9: ==36÷ = :45= (填小数)