1+2+1=4水泥用1×1/4=1/4立方沙子用1×2/4=1/2立方石子用1×1/4=1/4立方回答完毕~有疑问请追问，我一定尽快回复你~无疑问请点击【采纳】，同时预祝学习进步~\(^o^)/~我不是学霸，叫我赌神~\(^o^)/~~\(^o^)/~~\(^o^)/~~\(^o^)/~
