酥糖总价+水果糖总价+奶糖总价=什锦糖总价
设:奶糖每千克x元
2×4.4+3×4.2+5x=5.74×﹙2+3+5﹚
8.8+12.6+5x=57.4
5x=57.4-21.4
5x=36
x=7.2
答:奶糖每千克7.2元.