A path in a network has 3 activities. Their standard deviations are 1.5, 0.8 and 1.3. Find the path standard deviation. Steps (Problems 1) Imagine 3 activities in a path (means in a sequence). This implies 1st or 2nd activity parameters (such as duration) will augment the entire path parameter. To find the path standard deviation, you need to consider the standard deviations of each activity in the path. But standard deviations cant simply be added together since they are calculated using square roots. So, first, convert the standard deviations into variances. The steps to find the path standard deviation are as follows: 1. Square each of the individual standard deviations: 2. Sum the squared standard deviations: (path variance) 3. Take the square root of the sum: (path standard deviation)