Q: Mac Shutting Down Randomily Yosemite?

Ever since I updated to Yosemite, my computer shuts down randomly at least twice a day. My computer doesn't shut down if it is being charged.

Thanks

My mac specs are:

Model Name: MacBook Pro

  Model Identifier: MacBookPro7,1

  Processor Name: Intel Core 2 Duo

  Processor Speed: 2.4 GHz

  Number of Processors: 1

  Total Number of Cores: 2

  L2 Cache: 3 MB

  Memory: 4 GB

  Bus Speed: 1.07 GHz

  Boot ROM Version: MBP71.0039.B0E

  SMC Version (system): 1.62f7

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