down loads on goole play get stuck on install

I recently reset tablet to factory default. Now when I try to update existing apps some of them seem to get hung up during the install process. The get over half way then just seem to stop install,never even getting to finish the download. WiFi is @ excellent. status I have tried clearing cache for Google play. Also take an unusually long time to download a game, did the same thing got over half way seem to stop.after opening and closing Google play several times it it finally downloaded. Is that normal ? Please help