SOLUTION: You want to put a 2-inch thick layer of topsoil for a new 30 ft by 22 ft garden. The dirt store sells by the cubic yards. How many cubic yards will you need to order? The store onl
Question 1175099: You want to put a 2-inch thick layer of topsoil for a new 30 ft by 22 ft garden. The dirt store sells by the cubic yards. How many cubic yards will you need to order? The store only sells in increments of 1/4 cubic yards. Answer by ikleyn(52879) (Show Source):
The volume of soil you need is 2 inches x 30 ft x 22 ft = = 5*22 = 110 cubic feet = cubic yards = 4.07 cubic yards.
With the error less than 2%, 4.07 cubic yards is the same as 4 cubic yards.
In this area of human activity, 2% error is traditionally considered as zero,
so you will make it correctly ordering 4 cubic yards of topsoil.
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In scientific experiments an allowable level of experimental error is 2%.
In engineering, allowable level of experimental error is traditionally about 5%.
In human's everyday life and activity, allovable level of errors is about 7 - 8 - 10%.