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Answer: Look in the table at the end of the chapter and find that a selected proportion of 10% results in a selection intensity of 1.755. This means that this selected top 10% on average performs 1.755 standard deviations better than the population average. It will depend on the variance for the trait how much better that is in trait units: 1.755 *3.0 = 5.265 seconds. This is a bit optimistic because we were not able to estimate the genetic potential 100% accurately. In fact, it was only 24% accurate (rIH = 0.24). Combining all information results in: ΔG = i * rIH * σa = 1.755 * 0.24 * 0.3 = 1.26 seconds. The example is about improving running speed, so the next generation will be 1.26 sec faster: 117.0 – 1.26 = 115.74 seconds.