Answer
4.73%
Work Step by Step
The greatest possible percent error is determined by dividing the greater difference in area by the measured area. The greatest possible area is found with the maximum values of the sides given, and the smallest possible area is found with the minimum values of the sides given.
Maximum value for sides: $18.5+.25 = 18.75$ and $7.5+.25=7.75$ Minimum value for sides: $18.5 - .25 = 18.25$ and $7.5-.25 = 7.25$
Maximum area: $18.75 * 7.75 = 145.3125$ meters squared Minimum area: $18.25 * 7.25 = 132.3125$ meters squared
Measured area: $18.5 * 7.5 = 138.75$ meters squared
absolute value of (minimum area - measured area) = $abs(132.3125-138.75)$
$abs(132.3125-138.75) = abs(-6.4375) = 6.4375$
absolute value of (maximum area - measured area) =
$abs(145.3125-138.75) = abs(6.5625) = 6.5625$
Error percentage: $6.5625/138.75 = .04729 = 4.73$ percent
