While amsh's answer definitely gives you what you need for interview purposes, for any visual learners like me, here's what running through all possible paths ends up looking like.

Another thing I might consider bringing up in an interview context would be the intuitive reasoning behind why it works out this way. In other words, just explaining that a 15% loss on \$130 has a larger gross impact than a 15% gain on \$70. Then you can talk about geometric returns, high water marks, etc. to demonstrate that you understand the financial/business relevance of what's going on mathematically.
--
For reference, the R code I threw together to make the graph above:
r = c(5, -5, 10, -10, 15, -15) * 0.01
x0 = 100
k = length(r)
n = factorial(k)
r = sort(r)
permList = combinat::permn(r)
results = matrix(NA, n, k+1)
results[,1] = x0
if (n != length(permList)) stop("factorial(length(r)) != length([permutations])")
for (i in 1:n)
for (j in 2:(k+1))
results[i,j] = results[i,j-1] + results[i,j-1]*permList[[i]][j-1]
if (!("Euclid" %in% names(windowsFonts())))
windowsFonts(Euclid=windowsFont("Euclid"))
par(family="Euclid", mar=c(2.5,2.5,0.5,0.5), mgp=c(1.5,0.5,0), cex=0.75)
matplot(t(results), pch=19, type='o', col=rgb(1:n/n,0,n:1/n,n/(k*n)), xlab='', ylab='', main='')
grid(lty=1, col=rgb(0,0,0,0.2))
abline(h=x0, lty=2)
title(xlab=expression(t), ylab=expression(X[t]), font=3)