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Find the number of liters in 12.8 gal of gasoline. round to the nearest hundredths

The u-drive rent-a-truck company plans to spend $13 million on 320 new vehicles. each commercial van will cost $25 comma 000, each small truck $50 comma 000, and each large truck  $80 comma 000. past experience shows that they need twice as many vans as small trucks. how many of each type of vehicle can they buy?

The standard deviation for a set of data is 5.5. the mean is 265. what is the margin of error?