复合单位

使用复合单位，如速度（距离÷时间）、单价（成本÷数量）和密度（质量÷体积）；解决涉及复合单位的问题。

Use compound units such as speed (distance ÷ time), unit pricing (cost ÷ quantity), and density (mass ÷ volume); solve problems involving compound units

学习证据 / Evidence

• 根据距离和时间计算平均速度，必要时在千米/小时和米/秒之间进行换算。
• 比较两种不同数量商品的单价，找出更划算的选择。
• 运用密度公式，在已知其中两个量的情况下求出质量、体积或密度。

• Calculate average speed given distance and time, converting between km/h and m/s if needed
• Compare unit prices of two products sold in different quantities to find the better deal
• Use the density formula to find mass, volume, or density given the other two values

评估问题 / Assessment

如果一辆汽车在2.5小时内行驶了150英里，{{name}}能算出它的平均速度吗——并运用同样的思路来解决每千克价格或材料密度的问题吗？

If a car travels 150 miles in 2.5 hours, can {{name}} work out its average speed — and use the same idea to solve problems about price per kilogram or density of a material?