How much time passed between Jesus' resurrection and Pentecost?

Les explains that Christ had just been crucified at the time of Passover, and the disciples were waiting for Pentecost, which would be the fiftieth day. He points out that 40 days were spent in His post-resurrection ministry to them, and then they waited another ten days. So the fiftieth day arrived. Les also notes that these Jewish feast days brought Jews from the whole known world to Jerusalem, and the Temple was still operating. No one had told these Jewish believers to cast aside Temple worship or the Law, so they were still practicing these seven feast days. At Pentecost, they were all with one accord in one place, and suddenly a sound from heaven as of a rushing mighty wind filled the house where they were sitting.