一个三角形的三内角的度数比是2:3:4,这个三角形是 角三角形,最小角的度数是 .
9÷ =0.6= :20=30: .
= :15==6÷ = (填小数)
:8=15÷ ==9: .
==12÷ = :20= (小数)
15÷ === %= (小数)