Since it's been given that the percent error is less than 5%, the estimated length will be:
A.) Minimum : -5% of 58 1/2 inches
[tex]\text{ 58 }\frac{1}{2}\text{ x }\frac{100\text{ - 5}}{100}\text{ = }\frac{116\text{ + 1}}{\text{ 2}}\text{ x }\frac{\text{ 95}}{\text{ 100}}[/tex][tex]\text{ = }\frac{\text{ 117}}{\text{ 2}}\text{ x }\frac{\text{ 95}}{\text{ 100}}\text{ = }\frac{\text{ 11,115}}{\text{ 200}}[/tex][tex]\text{ = 55.575 or 55}\frac{23}{40}\text{ inches}[/tex]
B.) Maximum : +5% of 58 1/2 inches
[tex]\text{ 58}\frac{1}{2}\text{ x }\frac{\text{ 100 + 5}}{\text{ 100}}\text{ = }\frac{\text{ 117}}{2}\text{ x }\frac{105}{\text{ 100}}[/tex][tex]\text{ =}\frac{12,\text{ 285}}{200}[/tex][tex]\text{ = 61.425 or 61}\frac{17}{40}\text{ inches}[/tex]
Therefore, Margarets's esitmated length is between 55 23/40 inches and 61 17/40 inches.