A pacer walks along a 90m course on fairly level ground for a survey party and counted 99.0, 100.0, 101.50, 103.0, 105.50 and 104.0 paces respectively. He then started walking an unknown distance OP which he recorded 174.0, 175.50, 176,0, and 177.0 paces. Determine the following:

A] Unknown distance OP

B] Relative Precision of the measurement if the taped length of OP is 155.0 meters.(Simplify to the nearest unit fraction)