英语数学题,同志们,快啊,a car travels 10 km at a speed of 100km/h,40km
英语数学题,同志们,快啊,
a car travels 10 km at a speed of 100km/h,40km at 80km/h and the third distance at 50km/h if the average speed for the entire trip is 70km/h ,what's the length of the third distance?
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i have a number .if i multiply the number by 4 and subtract 12 ,i get twice as much as when i first substract 12 and then multiply the number