一条有关RATE的数学题,(a) Bob,by himself,can paint four rooms in 10 hours.If he hires Peter to help,they can do the same job together in 6 hours.If he lets Peter work alone,how long will it take for Peter to paint the four rooms?(b) In part(a)

一条有关RATE的数学题,(a) Bob,by himself,can paint four rooms in 10 hours.If he hires Peter to help,they can do the same job together in 6 hours.If he lets Peter work alone,how long will it take for Peter to paint the four rooms?(b) In part(a) 英语单词（有关计算机的）：payload rate,line rate,overhead rate payload rate,line rate,overhead rate 一条难的数学题 数学题：有关立体几何的! 有关韩信点兵的数学题 有关立方根的数学题 一道有关不等式的数学题ax+(1-a)/x-1 foreign rate 与exchange rate的区别 currency rate和exchange rate的区别 spot rate 与forward rate 的关系 一条难难的数学题 有关现在完成时与一般过去时的一个选择题You are late again,Bob!Sorry,my car________down on the way.A.broke B.has broken请说明一下原因 Rate的中文含义 Exchange Rate的意思? 初一有关绝对值的数学题 有关二次根式的数学题. 寻找有关圆周角的数学题!~~~~~ 有关三角函数的初中数学题