96. Processing a batch of parts, if A works for 5 hours first, then B joins to work together, A will have made 400 more parts than B when completed; if B works for 5 hours first, then A joins to work together, B will have made 40 more parts than A when completed. If A and B start working together from the beginning, how many more parts will A have made than B when completed?
Reference answer: 180