What is the margin of error for a sample size of 348 people

You are remodeling your kitchen. you’ve contacted two tiling companies who gladly told you how long it took their workers to tile of a similar size jim completed half the floor in 8 hours. pete completed half of the other floor in 7 hours. if pete can lay 20 more tiles per hour than jim, at what rate can jim lay tiles

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George writes the mixed number as sum and uses the distributive property 1/2.-2/5=1/2-2+2/5=1/2